Conventional long name	United States of America
Common name	the United States
Image coat	US-GreatSeal-Obverse.svg
Length	1776–present
Symbol type	Great Seal
National motto	In God We Trust(official)(traditional)(Latin: Out of Many, One)
Map width	220px
National anthem	"The Star-Spangled Banner"
Official languages	None at federal level
Languages type	National language
Languages	English (de facto)
Capital	Washington, D.C.
Largest city	New York City
Government type	Federal presidential constitutional republic
Leader title1	President
Leader name1	Barack Obama (D)
Leader title2	Vice President
Leader name2	Joe Biden (D)
Leader title3
Leader name3	John Boehner (R)
Leader title4	Chief Justice
Leader name4	John Roberts
Legislature	Congress
Upper house	Senate
Lower house	House of Representatives
Sovereignty type	Independence
Established event1	Declared
Established date1	July 4, 1776
Established event2	Recognized
Established date2	September 3, 1783
Established event3	Current constitution
Established date3	June 21, 1788
Area footnote
Area sq mi	3794101
Area km2	9826675
Area rank	3rd/4th
Area magnitude	1 E12
Percent water	6.76
Population estimate	}}

|population_estimate_year = 2011 |population_estimate_rank = 3rd |population_density_km2 = 33.7 |population_density_sq_mi = 87.4 |GDP_PPP_year = 2010 |GDP_PPP = $14.780 trillion |GDP_PPP_rank = 1st |GDP_PPP_per_capita = $47,123 |GDP_PPP_per_capita_rank = 6th |GDP_nominal = $14.780 trillion |GDP_nominal_rank = 1st |GDP_nominal_year = 2010 |GDP_nominal_per_capita = $47,132 |GDP_nominal_per_capita_rank = 9th |HDI_year = 2010 |HDI = 0.902 |HDI_rank = 4th |HDI_category = very high |EF_year = 2007 |EF = 8.0 gha |EF_rank = 6th |Gini = 45.0 |Gini_rank = 39th |Gini_year = 2007 |currency = United States dollar ($) |currency_code = USD |country_code = USA |utc_offset = −5 to −10 |utc_offset_DST = −4 to −10 |cctld = .us .gov .mil .edu |calling_code = +1 |date_format = m/d/yy (AD) |drives_on = right |demonym = American |footnotes = a. English is the official language of at least 28 states—some sources give a higher figure, based on differing definitions of "official". English and Hawaiian are both official languages in the state of Hawaii.

b. English is the de facto language of American government and the sole language spoken at home by 80% of Americans age five and older. Spanish is the second most commonly spoken language.

c. Whether the United States or the People's Republic of China is larger is disputed. The figure given is from the U.S. Central Intelligence Agency's World Factbook. Other sources give smaller figures. All authoritative calculations of the country's size include only the 50 states and the District of Columbia, not the territories.

d. The population estimate includes people whose usual residence is in the fifty states and the District of Columbia, including noncitizens. It does not include either those living in the territories, amounting to more than 4 million U.S. citizens (most in Puerto Rico), or U.S. citizens living outside the United States. }}

The United States of America (also called the United States, the States, the U.S., the USA, and America) is a federal constitutional republic comprising fifty states and a federal district. The country is mostly in central North America, where its forty-eight contiguous states and Washington, D.C., the capital district, lie between the Pacific and Atlantic Oceans, bordered by Canada to the north and Mexico to the south. The state of Alaska is in the northwest of the continent, with Canada to the east and Russia to the west across the Bering Strait. The state of Hawaii is an archipelago in the mid-Pacific. The country also possesses several territories in the Pacific and Caribbean.

At 3.79 million square miles (9.83 million km²) and with over 312 million people, the United States is the third or fourth largest country by total area, and the third largest by both land area and population. It is one of the world's most ethnically diverse and multicultural nations, the product of large-scale immigration from many countries. The U.S. economy is the world's largest national economy, with an estimated 2010 GDP of $14.780 trillion (23% of nominal global GDP and 20% of global GDP at purchasing-power parity).

Indigenous peoples have inhabited what is now the mainland United States for between 12,000 and 40,000 years since the Paleo-Indians crossed the Bearing land bridge from Asia to North America. This Native American population was greatly reduced by disease and warfare after European contact. The United States was founded by thirteen British colonies located along the Atlantic seaboard. On July 4, 1776, they issued the Declaration of Independence, which proclaimed their right to self-determination and their establishment of a cooperative union. The rebellious states defeated the British Empire in the American Revolution, the first successful colonial war of independence. The current United States Constitution was adopted on September 17, 1787; its ratification the following year made the states part of a single republic with a strong central government. The Bill of Rights, comprising ten constitutional amendments guaranteeing many fundamental civil rights and freedoms, was ratified in 1791.

Through the 19th century, the United States displaced native tribes, acquired the Louisiana territory from France, Florida from Spain, part of the Oregon Country from the United Kingdom, Alta California and New Mexico from Mexico, Alaska from Russia, and annexed the Republic of Texas and the Republic of Hawaii. Disputes between the agrarian South and industrial North over the expansion of the institution of slavery and states' rights provoked the Civil War of the 1860s. The North's victory prevented a permanent split of the country and led to the end of legal slavery in the United States. By the 1870s, its national economy was the world's largest. The Spanish–American War and World War I confirmed the country's status as a military power. It emerged from World War II as the first country with nuclear weapons and a permanent member of the United Nations Security Council. The end of the Cold War and the dissolution of the Soviet Union left the United States as the sole superpower. The country accounts for 41% of global military spending, and it is a leading economic, political, and cultural force in the world.

Etymology

In 1507, German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere "America" after Italian explorer and cartographer Amerigo Vespucci. The former British colonies first used the country's modern name in the 1776 Declaration of Independence, the "unanimous Declaration of the thirteen united States of America". On November 15, 1777, the Second Continental Congress adopted the Articles of Confederation, which states, "The Stile of this Confederacy shall be 'The United States of America.'" The Franco-American treaties of 1778 used "United States of North America", but from July 11, 1778, "United States of America" was used on the country's bills of exchange, and it has been the official name ever since.

The short form "United States" is also standard. Other common forms include the "U.S.", the "USA", and "America". Colloquial names include the "U.S. of A." and, internationally, the "States". "Columbia", a once popular name for the United States, derives from Christopher Columbus; it appears in the name "District of Columbia".

The standard way to refer to a citizen of the United States is as an "American". Although "United States" is the official appositional term, "American" and "U.S." are more commonly used to refer to the country adjectivally ("American values", "U.S. forces"). "American" is rarely used in English to refer to people not connected to the United States.

The phrase "United States" was originally treated as plural—e.g., "the United States are"—including in the Thirteenth Amendment to the United States Constitution, ratified in 1865. It became common to treat it as singular—e.g., "the United States is"—after the end of the Civil War. The singular form is now standard; the plural form is retained in the idiom "these United States".

Geography and environment

The land area of the contiguous United States is approximately . Alaska, separated from the contiguous United States by Canada, is the largest state at . Hawaii, occupying an archipelago in the central Pacific, southwest of North America, has just over . The United States is the world's third or fourth largest nation by total area (land and water), ranking behind Russia and Canada and just above or below China. The ranking varies depending on how two territories disputed by China and India are counted and how the total size of the United States is measured: calculations range from to to . Including only land area, the United States is third in size behind Russia and China, just ahead of Canada.

The coastal plain of the Atlantic seaboard gives way further inland to deciduous forests and the rolling hills of the Piedmont. The Appalachian Mountains divide the eastern seaboard from the Great Lakes and the grasslands of the Midwest. The Mississippi–Missouri River, the world's fourth longest river system, runs mainly north–south through the heart of the country. The flat, fertile prairie of the Great Plains stretches to the west, interrupted by a highland region in the southeast. The Rocky Mountains, at the western edge of the Great Plains, extend north to south across the country, reaching altitudes higher than 14,000 feet (4,300 m) in Colorado. Farther west are the rocky Great Basin and deserts such as the Mojave. The Sierra Nevada and Cascade mountain ranges run close to the Pacific coast. At 20,320 feet (6,194 m), Alaska's Mount McKinley is the tallest peak in the country and in North America. Active volcanoes are common throughout Alaska's Alexander and Aleutian Islands, and Hawaii consists of volcanic islands. The supervolcano underlying Yellowstone National Park in the Rockies is the continent's largest volcanic feature. The United States, with its large size and geographic variety, includes most climate types. To the east of the 100th meridian, the climate ranges from humid continental in the north to humid subtropical in the south. The southern tip of Florida is tropical, as is Hawaii. The Great Plains west of the 100th meridian are semi-arid. Much of the Western mountains are alpine. The climate is arid in the Great Basin, desert in the Southwest, Mediterranean in coastal California, and oceanic in coastal Oregon and Washington and southern Alaska. Most of Alaska is subarctic or polar. Extreme weather is not uncommon—the states bordering the Gulf of Mexico are prone to hurricanes, and most of the world's tornadoes occur within the country, mainly in the Midwest's Tornado Alley.

The U.S. ecology is considered "megadiverse": about 17,000 species of vascular plants occur in the contiguous United States and Alaska, and over 1,800 species of flowering plants are found in Hawaii, few of which occur on the mainland. The United States is home to more than 400 mammal, 750 bird, and 500 reptile and amphibian species. About 91,000 insect species have been described. The Endangered Species Act of 1973 protects threatened and endangered species and their habitats, which are monitored by the United States Fish and Wildlife Service. There are fifty-eight national parks and hundreds of other federally managed parks, forests, and wilderness areas. Altogether, the government owns 28.8% of the country's land area. Most of this is protected, though some is leased for oil and gas drilling, mining, logging, or cattle ranching; 2.4% is used for military purposes.

Political divisions

The United States is a federal union of fifty states. The original thirteen states were the successors of the thirteen colonies that rebelled against British rule. Early in the country's history, three new states were organized on territory separated from the claims of the existing states: Kentucky from Virginia; Tennessee from North Carolina; and Maine from Massachusetts. Most of the other states have been carved from territories obtained through war or purchase by the U.S. government. One set of exceptions comprises Vermont, Texas, and Hawaii: each was an independent republic before joining the union. During the American Civil War, West Virginia broke away from Virginia. The most recent state—Hawaii—achieved statehood on August 21, 1959. The states do not have the right to secede from the union.

The states compose the vast bulk of the U.S. land mass; the two other areas considered integral parts of the country are the District of Columbia, the federal district where the capital, Washington, is located; and Palmyra Atoll, an uninhabited but incorporated territory in the Pacific Ocean. The United States also possesses five major overseas territories: Puerto Rico and the United States Virgin Islands in the Caribbean; and American Samoa, Guam, and the Northern Mariana Islands in the Pacific. Those born in the major territories (except for American Samoa) possess U.S. citizenship. American citizens residing in the territories have many of the same rights and responsibilities as citizens residing in the states; however, they are generally exempt from federal income tax, may not vote for president, and have only nonvoting representation in the U.S. Congress.

History

Native American and European settlement

The indigenous peoples of the U.S. mainland, including Alaska Natives, are believed to have migrated from Asia, beginning between 12,000 and 40,000 years ago. Some, such as the pre-Columbian Mississippian culture, developed advanced agriculture, grand architecture, and state-level societies. After Europeans began settling the Americas, many millions of indigenous Americans died from epidemics of imported diseases such as smallpox.

In 1492, Genoese explorer Christopher Columbus, under contract to the Spanish crown, reached several Caribbean islands, making first contact with the indigenous people. On April 2, 1513, Spanish conquistador Juan Ponce de León landed on what he called "La Florida"—the first documented European arrival on what would become the U.S. mainland. Spanish settlements in the region were followed by ones in the present-day southwestern United States that drew thousands through Mexico. French fur traders established outposts of New France around the Great Lakes; France eventually claimed much of the North American interior, down to the Gulf of Mexico. The first successful English settlements were the Virginia Colony in Jamestown in 1607 and the Pilgrims' Plymouth Colony in 1620. The 1628 chartering of the Massachusetts Bay Colony resulted in a wave of migration; by 1634, New England had been settled by some 10,000 Puritans. Between the late 1610s and the American Revolution, about 50,000 convicts were shipped to Britain's American colonies. Beginning in 1614, the Dutch settled along the lower Hudson River, including New Amsterdam on Manhattan Island.

In 1674, the Dutch ceded their American territory to England; the province of New Netherland was renamed New York. Many new immigrants, especially to the South, were indentured servants—some two-thirds of all Virginia immigrants between 1630 and 1680. By the turn of the 18th century, African slaves were becoming the primary source of bonded labor. With the 1729 division of the Carolinas and the 1732 colonization of Georgia, the thirteen British colonies that would become the United States of America were established. All had local governments with elections open to most free men, with a growing devotion to the ancient rights of Englishmen and a sense of self-government stimulating support for republicanism. All legalized the African slave trade. With high birth rates, low death rates, and steady immigration, the colonial population grew rapidly. The Christian revivalist movement of the 1730s and 1740s known as the Great Awakening fueled interest in both religion and religious liberty. In the French and Indian War, British forces seized Canada from the French, but the francophone population remained politically isolated from the southern colonies. Excluding the Native Americans (popularly known as "American Indians"), who were being displaced, those thirteen colonies had a population of 2.6 million in 1770, about one-third that of Britain; nearly one in five Americans were black slaves. Though subject to British taxation, the American colonials had no representation in the Parliament of Great Britain.

Independence and expansion

Tensions between American colonials and the British during the revolutionary period of the 1760s and early 1770s led to the American Revolutionary War, fought from 1775 to 1781. On June 14, 1775, the Continental Congress, convening in Philadelphia, established a Continental Army under the command of George Washington. Proclaiming that "all men are created equal" and endowed with "certain unalienable Rights", the Congress adopted the Declaration of Independence, drafted largely by Thomas Jefferson, on July 4, 1776. That date is now celebrated annually as America's Independence Day. In 1777, the Articles of Confederation established a weak confederal government that operated until 1789.

After the British defeat by American forces assisted by the French and Spanish, Great Britain recognized the independence of the United States and the states' sovereignty over American territory west to the Mississippi River. Those wishing to establish a strong national government with powers of taxation organized a constitutional convention in 1787. The United States Constitution was ratified in 1788, and the new republic's first Senate, House of Representatives, and president—George Washington—took office in 1789. The Bill of Rights, forbidding federal restriction of personal freedoms and guaranteeing a range of legal protections, was adopted in 1791.

Attitudes toward slavery were shifting; a clause in the Constitution protected the transatlantic slave trade only until 1808. The Northern states abolished slavery between 1780 and 1804, leaving the slave states of the South as defenders of the "peculiar institution". The Second Great Awakening, beginning about 1800, made evangelicalism a force behind various social reform movements, including abolitionism.

Americans' eagerness to expand westward prompted a long series of Indian Wars. The Louisiana Purchase of French-claimed territory under President Thomas Jefferson in 1803 almost doubled the nation's size. The War of 1812, declared against Britain over various grievances and fought to a draw, strengthened U.S. nationalism. A series of U.S. military incursions into Florida led Spain to cede it and other Gulf Coast territory in 1819. The Trail of Tears in the 1830s exemplified the Indian removal policy that stripped the native peoples of their land. The United States annexed the Republic of Texas in 1845, amid a period when the concept of Manifest Destiny was becoming popular. The 1846 Oregon Treaty with Britain led to U.S. control of the present-day American Northwest. The U.S. victory in the Mexican-American War resulted in the 1848 cession of California and much of the present-day American Southwest. The California Gold Rush of 1848–49 further spurred western migration. New railways made relocation easier for settlers and increased conflicts with Native Americans. Over a half-century, up to 40 million American bison, or buffalo, were slaughtered for skins and meat and to ease the railways' spread. The loss of the buffalo, a primary resource for the plains Indians, was an existential blow to many native cultures.

Civil War and industrialization

Tensions between slave and free states mounted with arguments over the relationship between the state and federal governments, as well as violent conflicts over the spread of slavery into new states. Abraham Lincoln, candidate of the largely antislavery Republican Party, was elected president in 1860. Before he took office, seven slave states declared their secession—which the federal government maintained was illegal—and formed the Confederate States of America. With the Confederate attack upon Fort Sumter, the Civil War began and four more slave states joined the Confederacy. Lincoln's Emancipation Proclamation in 1863 declared slaves in the Confederacy to be free. Following the Union victory in 1865, three amendments to the U.S. Constitution ensured freedom for the nearly four million African Americans who had been slaves, made them citizens, and gave them voting rights. The war and its resolution led to a substantial increase in federal power. The war remains the deadliest conflict in American history, resulting in the deaths of 620,000 soldiers.

After the war, the assassination of Lincoln radicalized Republican Reconstruction policies aimed at reintegrating and rebuilding the Southern states while ensuring the rights of the newly freed slaves. The resolution of the disputed 1876 presidential election by the Compromise of 1877 ended Reconstruction; Jim Crow laws soon disenfranchised many African Americans. In the North, urbanization and an unprecedented influx of immigrants from Southern Southern and Eastern Europe hastened the country's industrialization. The wave of immigration, lasting until 1929, provided labor and transformed American culture. National infrastructure development spurred economic growth. The 1867 Alaska Purchase from Russia completed the country's mainland expansion. The Wounded Knee Massacre in 1890 was the last major armed conflict of the Indian Wars. In 1893, the indigenous monarchy of the Pacific Kingdom of Hawaii was overthrown in a coup led by American residents; the United States annexed the archipelago in 1898. Victory in the Spanish–American War the same year demonstrated that the United States was a world power and led to the annexation of Puerto Rico, Guam, and the Philippines. The Philippines gained independence a half-century later; Puerto Rico and Guam remain U.S. territories.

World War I, Great Depression, and World War II

At the outbreak of World War I in 1914, the United States remained neutral. Most Americans sympathized with the British and French, although many opposed intervention. In 1917, the United States joined the Allies, and the American Expeditionary Forces helped to turn the tide against the Central Powers. After the war, the Senate did not ratify the Treaty of Versailles, which established the League of Nations. The country pursued a policy of unilateralism, verging on isolationism. In 1920, the women's rights movement won passage of a constitutional amendment granting women's suffrage. The prosperity of the Roaring Twenties ended with the Wall Street Crash of 1929 that triggered the Great Depression. After his election as president in 1932, Franklin D. Roosevelt responded with the New Deal, a range of policies increasing government intervention in the economy, including the establishment of the Social Security system. The Dust Bowl of the mid-1930s impoverished many farming communities and spurred a new wave of western migration. The United States, effectively neutral during World War II's early stages after Nazi Germany's invasion of Poland in September 1939, began supplying materiel to the Allies in March 1941 through the Lend-Lease program. On December 7, 1941, the Empire of Japan launched a surprise attack on Pearl Harbor, prompting the United States to join the Allies against the Axis powers as well as the internment of Japanese Americans by the thousands. Participation in the war spurred capital investment and industrial capacity. Among the major combatants, the United States was the only nation to become richer—indeed, far richer—instead of poorer because of the war. Allied conferences at Bretton Woods and Yalta outlined a new system of international organizations that placed the United States and Soviet Union at the center of world affairs. As victory was won in Europe, a 1945 international conference held in San Francisco produced the United Nations Charter, which became active after the war. The United States, having developed the first nuclear weapons, used them on the Japanese cities of Hiroshima and Nagasaki in August. Japan surrendered on September 2, ending the war.

Cold War and protest politics

The United States and Soviet Union jockeyed for power after World War II during the Cold War, dominating the military affairs of Europe through NATO and the Warsaw Pact, respectively. While they engaged in proxy wars and developed powerful nuclear arsenals, the two countries avoided direct military conflict. Resisting leftist land and income redistribution projects around the world, the United States often supported authoritarian governments. American troops fought Communist Chinese forces in the Korean War of 1950–53. The House Un-American Activities Committee pursued a series of investigations into suspected leftist subversion, while Senator Joseph McCarthy became the figurehead of anticommunist sentiment.

The 1961 Soviet launch of the first manned spaceflight prompted President John F. Kennedy's call for the United States to be first to land "a man on the moon", achieved in 1969. Kennedy also faced a tense nuclear showdown with Soviet forces in Cuba. Meanwhile, the United States experienced sustained economic expansion. A growing civil rights movement, symbolized and led by African Americans such as Rosa Parks, Martin Luther King, Jr., and James Bevel, used nonviolence to confront segregation and discrimination. Following Kennedy's assassination in 1963, the Civil Rights Act of 1964 and Voting Rights Act of 1965 were passed under President Lyndon B. Johnson. He also signed into law the Medicare and Medicaid programs. Johnson and his successor, Richard Nixon, expanded a proxy war in Southeast Asia into the unsuccessful Vietnam War. A widespread countercultural movement grew, fueled by opposition to the war, black nationalism, and the sexual revolution. Betty Friedan, Gloria Steinem, and others led a new wave of feminism that sought political, social, and economic equality for women.

As a result of the Watergate scandal, in 1974 Nixon became the first U.S. president to resign, to avoid being impeached on charges including obstruction of justice and abuse of power. The Jimmy Carter administration of the late 1970s was marked by stagflation and the Iran hostage crisis. The election of Ronald Reagan as president in 1980 heralded a rightward shift in American politics, reflected in major changes in taxation and spending priorities. His second term in office brought both the Iran-Contra scandal and significant diplomatic progress with the Soviet Union. The subsequent Soviet collapse ended the Cold War.

Contemporary era

Under President George H. W. Bush, the United States took a lead role in the UN–sanctioned Gulf War. The longest economic expansion in modern U.S. history—from March 1991 to March 2001—encompassed the Bill Clinton administration and the dot-com bubble. A civil lawsuit and sex scandal led to Clinton's impeachment in 1998, but he remained in office. The 2000 presidential election, one of the closest in American history, was resolved by a U.S. Supreme Court decision—George W. Bush, son of George H. W. Bush, became president.

On September 11, 2001, al-Qaeda terrorists struck the World Trade Center in New York City and The Pentagon near Washington, D.C., killing nearly three thousand people. In response, the Bush administration launched the global War on Terror, invading Afghanistan and removing the Taliban government and al-Qaeda training camps. Taliban insurgents continue to fight a guerrilla war. In 2002, the Bush administration began to press for regime change in Iraq on controversial grounds. Forces of a so-called Coalition of the Willing invaded Iraq in 2003, ousting Saddam Hussein. In 2005, Hurricane Katrina caused severe destruction along much of the Gulf Coast, devastating New Orleans. In 2008, amid a global economic recession, the first African American president, Barack Obama, was elected. In 2010, major health care and financial system reforms were enacted.

Government, elections, and politics

The United States is the world's oldest surviving federation. It is a constitutional republic and representative democracy, "in which majority rule is tempered by minority rights protected by law". The government is regulated by a system of checks and balances defined by the U.S. Constitution, which serves as the country's supreme legal document. In the American federalist system, citizens are usually subject to three levels of government, federal, state, and local; the local government's duties are commonly split between county and municipal governments. In almost all cases, executive and legislative officials are elected by a plurality vote of citizens by district. There is no proportional representation at the federal level, and it is very rare at lower levels.

The federal government is composed of three branches:

Legislative: The bicameral Congress, made up of the Senate and the House of Representatives, makes federal law, declares war, approves treaties, has the power of the purse, and has the power of impeachment, by which it can remove sitting members of the government.

Executive: The president is the commander-in-chief of the military, can veto legislative bills before they become law, and appoints the members of the Cabinet (subject to Senate approval) and other officers, who administer and enforce federal laws and policies.

Judicial: The Supreme Court and lower federal courts, whose judges are appointed by the president with Senate approval, interpret laws and overturn those they find unconstitutional.

The House of Representatives has 435 voting members, each representing a congressional district for a two-year term. House seats are apportioned among the states by population every tenth year. As of the 2000 census, seven states have the minimum of one representative, while California, the most populous state, has fifty-three. The Senate has 100 members with each state having two senators, elected at-large to six-year terms; one third of Senate seats are up for election every other year. The president serves a four-year term and may be elected to the office no more than twice. The president is not elected by direct vote, but by an indirect electoral college system in which the determining votes are apportioned to the states and the District of Columbia. The Supreme Court, led by the Chief Justice of the United States, has nine members, who serve for life.

The state governments are structured in roughly similar fashion; Nebraska uniquely has a unicameral legislature. The governor (chief executive) of each state is directly elected. Some state judges and cabinet officers are appointed by the governors of the respective states, while others are elected by popular vote.

The original text of the Constitution establishes the structure and responsibilities of the federal government and its relationship with the individual states. Article One protects the right to the "great writ" of habeas corpus, and Article Three guarantees the right to a jury trial in all criminal cases. Amendments to the Constitution require the approval of three-fourths of the states. The Constitution has been amended twenty-seven times; the first ten amendments, which make up the Bill of Rights, and the Fourteenth Amendment form the central basis of Americans' individual rights. All laws and governmental procedures are subject to judicial review and any law ruled in violation of the Constitution is voided. The principle of judicial review, not explicitly mentioned in the Constitution, was declared by the Supreme Court in Marbury v. Madison (1803).

Parties and ideology

The United States has operated under a two-party system for most of its history. For elective offices at most levels, state-administered primary elections choose the major party nominees for subsequent general elections. Since the general election of 1856, the major parties have been the Democratic Party, founded in 1824, and the Republican Party, founded in 1854. Since the Civil War, only one third-party presidential candidate—former president Theodore Roosevelt, running as a Progressive in 1912—has won as much as 20% of the popular vote.

Within American political culture, the Republican Party is considered center-right or "conservative" and the Democratic Party is considered center-left or "liberal". The states of the Northeast and West Coast and some of the Great Lakes states, known as "blue states", are relatively liberal. The "red states" of the South and parts of the Great Plains and Rocky Mountains are relatively conservative.

The winner of the 2008 presidential election, Democrat Barack Obama, is the 44th U.S. president. The 2010 midterm elections saw the Republican Party take control of the House and make gains in the Senate, where the Democrats retain the majority. In the 112th United States Congress, the Senate comprises 51 Democrats, two independents who caucus with the Democrats, and 47 Republicans; the House comprises 240 Republicans and 192 Democrats—three seats are vacant. There are 29 Republican and 20 Democratic state governors, as well as one independent.

Foreign relations and military

The United States exercises global economic, political, and military influence. It is a permanent member of the United Nations Security Council and New York City hosts the United Nations Headquarters. It is a member of the G8, G20, and Organisation for Economic Co-operation and Development. Almost all countries have embassies in Washington, D.C., and many have consulates around the country. Likewise, nearly all nations host American diplomatic missions. However, Cuba, Iran, North Korea, Bhutan, Libya, and the Republic of China (Taiwan) do not have formal diplomatic relations with the United States.

The United States has a "special relationship" with the United Kingdom and strong ties with Canada, Australia, New Zealand, the Philippines, Japan, South Korea, Israel, and several European countries. It works closely with fellow NATO members on military and security issues and with its neighbors through the Organization of American States and free trade agreements such as the trilateral North American Free Trade Agreement with Canada and Mexico. In 2008, the United States spent a net $25.4 billion on official development assistance, the most in the world. As a share of America's large gross national income (GNI), however, the U.S. contribution of 0.18% ranked last among twenty-two donor states. By contrast, private overseas giving by Americans is relatively generous.

The president holds the title of commander-in-chief of the nation's armed forces and appoints its leaders, the secretary of defense and the Joint Chiefs of Staff. The United States Department of Defense administers the armed forces, including the Army, Navy, Marine Corps, and Air Force. The Coast Guard is run by the Department of Homeland Security in peacetime and the Department of the Navy in time of war. In 2008, the armed forces had 1.4 million personnel on active duty. The Reserves and National Guard brought the total number of troops to 2.3 million. The Department of Defense also employed about 700,000 civilians, not including contractors.

Military service is voluntary, though conscription may occur in wartime through the Selective Service System. American forces can be rapidly deployed by the Air Force's large fleet of transport aircraft, the Navy's eleven active aircraft carriers, and Marine Expeditionary Units at sea with the Navy's Atlantic and Pacific fleets. The military operates 865 bases and facilities abroad, and maintains deployments greater than 100 active duty personnel in 25 foreign countries. The extent of this global military presence has prompted some scholars to describe the United States as maintaining an "empire of bases".

Total U.S. military spending in 2008, more than $600 billion, was over 41% of global military spending and greater than the next fourteen largest national military expenditures combined. The per capita spending of $1,967 was about nine times the world average; at 4% of GDP, the rate was the second-highest among the top fifteen military spenders, after Saudi Arabia. The proposed base Department of Defense budget for 2012, $553 billion, is a 4.2% increase over 2011; an additional $118 billion is proposed for the military campaigns in Iraq and Afghanistan. As of September 2010, the United States is scheduled to have 96,000 troops deployed to Afghanistan, and 50,000 to Iraq. As of July 25, 2011, the United States had suffered 4,474 military fatalities during the Iraq War, and 1,680 during the War in Afghanistan.

Economy

The United States has a capitalist mixed economy, which is fueled by abundant natural resources, a well-developed infrastructure, and high productivity. According to the International Monetary Fund, the U.S. GDP of $15 trillion constitutes 23% of the gross world product at market exchange rates and over 20% of the gross world product at purchasing power parity (PPP). Though larger than any other nation's, its national GDP is about 5% smaller than the GDP of the European Union at PPP in 2008. The country ranks ninth in the world in nominal GDP per capita and sixth in GDP per capita at PPP. The U.S. dollar is the world's primary reserve currency.

The United States is the largest importer of goods and third largest exporter, though exports per capita are relatively low. In 2008, the total U.S. trade deficit was $696 billion. Canada, China, Mexico, Japan, and Germany are its top trading partners. In 2007, vehicles constituted both the leading import and leading export commodity. China is the largest foreign holder of U.S. public debt.

In 2009, the private sector was estimated to constitute 55.3% of the economy, with federal government activity accounting for 24.1% and state and local government activity (including federal transfers) the remaining 20.6%. While its economy has reached a postindustrial level of development and its service sector constitutes 67.8% of GDP, the United States remains an industrial power. The leading business field by gross business receipts is wholesale and retail trade; by net income it is manufacturing. Chemical products are the leading manufacturing field. The United States is the third largest producer of oil in the world, as well as its largest importer. It is the world's number one producer of electrical and nuclear energy, as well as liquid natural gas, sulfur, phosphates, and salt. While agriculture accounts for just under 1% of GDP, the United States is the world's top producer of corn and soybeans. Coca-Cola and McDonald's are the two most recognized brands in the world.

In August 2010, the American labor force comprised 154.1 million people. With 21.2 million people, government is the leading field of employment. The largest private employment sector is health care and social assistance, with 16.4 million people. About 12% of workers are unionized, compared to 30% in Western Europe. The World Bank ranks the United States first in the ease of hiring and firing workers. In 2009, the United States had the third highest labor productivity per person in the world, behind Luxembourg and Norway. It was fourth in productivity per hour, behind those two countries and the Netherlands. Compared to Europe, U.S. property and corporate income tax rates are generally higher, while labor and, particularly, consumption tax rates are lower.

Income and human development

According to the United States Census Bureau, the pretax median household income in 2007 was $49,777. The median ranged from $65,469 among Asian American households to $32,584 among African American households. Using purchasing power parity exchange rates, the overall median is similar to the most affluent cluster of developed nations. After declining sharply during the middle of the 20th century, poverty rates have plateaued since the early 1970s, with 11–15% of Americans below the poverty line every year, and 58.5% spending at least one year in poverty between the ages of 25 and 75. In 2009, 43.6 million Americans lived in poverty.

The U.S. welfare state is one of the least extensive in the developed world, reducing both relative poverty and absolute poverty by considerably less than the mean for rich nations, though combined private and public social expenditures per capita are relatively high. While the American welfare state effectively reduces poverty among the elderly, it provides relatively little assistance to the young. A 2007 UNICEF study of children's well-being in twenty-one industrialized nations ranked the United States next to last.

Between 1947 and 1979, real median income rose by over 80% for all classes, with the incomes of poor Americans rising faster than those of the rich. Since 1980, the United States has witnessed strong increases in productivity, low unemployment, and low inflation. However, income gains since 1980 have been slower than in previous decades, less widely shared, and accompanied by increased economic insecurity. Median household income has increased for all classes since 1980, largely owing to more dual-earner households, the closing of the gender gap, and longer work hours, but growth has been slower and strongly tilted toward the very top (see graph). Consequently, the share of income of the top 1%—21.8% of total reported income in 2005—has more than doubled since 1980, leaving the United States with the greatest income inequality among developed nations. The top 1% pays 27.6% of all federal taxes, while the top 10% pays 54.7%. Wealth, like income, is highly concentrated: The richest 10% of the adult population possesses 69.8% of the country's household wealth, the second-highest share among developed nations. The top 1% possesses 33.4% of net wealth. In 2010 the United Nations Development Programme ranked the United States 12th among 139 countries on its inequality-adjusted human development index (IHDI), eight places lower than in the standard HDI.

Infrastructure

Science and technology

The United States has been a leader in scientific research and technological innovation since the late 19th century. In 1876, Alexander Graham Bell was awarded the first U.S. patent for the telephone. Thomas Edison's laboratory developed the phonograph, the first long-lasting light bulb, and the first viable movie camera. Nikola Tesla pioneered alternating current, the AC motor, and radio. In the early 20th century, the automobile companies of Ransom E. Olds and Henry Ford popularized the assembly line. The Wright brothers, in 1903, made the first sustained and controlled heavier-than-air powered flight.

The rise of Nazism in the 1930s led many European scientists, including Albert Einstein and Enrico Fermi, to immigrate to the United States. During World War II, the Manhattan Project developed nuclear weapons, ushering in the Atomic Age. The Space Race produced rapid advances in rocketry, materials science, and computers. IBM, Apple Computer, and Microsoft refined and popularized the personal computer. The United States largely developed the ARPANET and its successor, the Internet. Today, 64% of research and development funding comes from the private sector. The United States leads the world in scientific research papers and impact factor. Americans possess high levels of technological consumer goods, and almost half of U.S. households have broadband Internet access. The country is the primary developer and grower of genetically modified food, representing half of the world's biotech crops.

Transportation

Personal transportation is dominated by automobiles, which operate on a network of 13 million roads, including the world's longest highway system. The world's second largest automobile market, the United States has the highest rate of per-capita vehicle ownership in the world, with 765 vehicles per 1,000 Americans. About 40% of personal vehicles are vans, SUVs, or light trucks. The average American adult (accounting for all drivers and nondrivers) spends 55 minutes driving every day, traveling .

Mass transit accounts for 9% of total U.S. work trips, ranking last in a survey of 17 countries. While transport of goods by rail is extensive, relatively few people use rail to travel. Light rail development has increased in recent years but, like high speed rail, is below European levels. Bicycle usage for work commutes is minimal.

The civil airline industry is entirely privately owned and has been largely deregulated since 1978, while most major airports are publicly owned. The four largest airlines in the world by passengers carried are American; Southwest Airlines is number one. Of the world's thirty busiest passenger airports, sixteen are in the United States, including the busiest, Hartsfield-Jackson Atlanta International Airport.

Energy

The United States energy market is 29,000 terawatt hours per year. Energy consumption per capita is 7.8 tons of oil equivalent per year, the 10th highest rate in the world. In 2005, 40% of this energy came from petroleum, 23% from coal, and 22% from natural gas. The remainder was supplied by nuclear power and renewable energy sources. The United States is the world's largest consumer of petroleum. For decades, nuclear power has played a limited role relative to many other developed countries, in part due to public perception in the wake of a 1979 accident. In 2007, several applications for new nuclear plants were filed. The United States has 27% of global coal reserves.

Education

American public education is operated by state and local governments, regulated by the United States Department of Education through restrictions on federal grants. Children are required in most states to attend school from the age of six or seven (generally, kindergarten or first grade) until they turn eighteen (generally bringing them through twelfth grade, the end of high school); some states allow students to leave school at sixteen or seventeen. About 12% of children are enrolled in parochial or nonsectarian private schools. Just over 2% of children are homeschooled.

The United States has many competitive private and public institutions of higher education. According to prominent international rankings, 13 or 15 American colleges and universities are ranked among the top 20 in the world. There are also local community colleges with generally more open admission policies, shorter academic programs, and lower tuition. Of Americans twenty-five and older, 84.6% graduated from high school, 52.6% attended some college, 27.2% earned a bachelor's degree, and 9.6% earned graduate degrees. The basic literacy rate is approximately 99%. The United Nations assigns the United States an Education Index of 0.97, tying it for 12th in the world.

Health

The United States life expectancy of 78.3 years at birth is ranked 36th among 194 United Nations member states; while above the world average, it falls short of the overall figure in Western Europe. Increasing obesity in the United States and health improvements elsewhere have contributed to lowering the country's rank in life expectancy from 1987 to 2007, from 11th to 42nd in the world. The infant mortality rate of 6.37 per thousand places the United States 42nd out of 221 countries, above average but behind all of Western Europe. Approximately one-third of the adult population is obese and an additional third is overweight; the obesity rate, the highest in the industrialized world, has more than doubled in the last quarter-century. Obesity-related type 2 diabetes is considered epidemic by health care professionals.

The U.S. health care system far outspends any other nation's, measured in both per capita spending and percentage of GDP. The World Health Organization ranked the U.S. health care system in 2000 as first in responsiveness, but 37th in overall performance.

Health care coverage in the United States is a combination of public and private efforts, and is not universal as in all other developed countries. In 2004, private insurance paid for 36% of personal health expenditures, private out-of-pocket payments covered 15%, and federal, state, and local governments paid for 44%. In 2005, 46.6 million Americans, 15.9% of the population, were uninsured, 5.4 million more than in 2001. The main cause of this rise is the drop in the number of Americans with employer-sponsored health insurance. The subject of uninsured and underinsured Americans is a major political issue. A 2009 study estimated that lack of insurance is associated with nearly 45,000 deaths a year. In 2006, Massachusetts became the first state to mandate universal health insurance. Federal legislation passed in early 2010 will create a near-universal health insurance system around the country by 2014.

Crime and law enforcement

Law enforcement in the United States is primarily the responsibility of local police and sheriff's departments, with state police providing broader services. Federal agencies such as the Federal Bureau of Investigation (FBI) and the U.S. Marshals Service have specialized duties. At the federal level and in almost every state, jurisprudence operates on a common law system. State courts conduct most criminal trials; federal courts handle certain designated crimes as well as certain appeals from the state systems. Federal law prohibits a variety of drugs, although states sometimes pass laws in conflict with federal regulations. The smoking age is generally 18 and the drinking age is generally 21.

Among developed nations, the United States has above-average levels of violent crime and particularly high levels of gun violence and homicide. There were 5.0 murders per 100,000 persons in 2009, 10.4% fewer than in 2000. Gun ownership rights are the subject of contentious political debate.

The United States has the highest documented incarceration rate and total prison population in the world. At the start of 2008, more than 2.3 million people were incarcerated, more than one in every 100 adults. The current rate is about seven times the 1980 figure, and over three times the figure in Poland, the Organisation for Economic Co-operation and Development (OECD) country with the next highest rate. African American males are jailed at about six times the rate of white males and three times the rate of Hispanic males. The country's high rate of incarceration is largely due to sentencing and drug policies.

Though it has been abolished in most Western nations, capital punishment is sanctioned in the United States for certain federal and military crimes, and in thirty-four states. Since 1976, when the U.S. Supreme Court reinstated the death penalty after a four-year moratorium, there have been more than 1,000 executions. In 2010, the country had the fifth highest number of executions in the world, following China, Iran, North Korea, and Yemen. In 2007, New Jersey became the first state to legislatively abolish the death penalty since the 1976 Supreme Court decision, followed by New Mexico in 2009 and Illinois in 2011.

Demographics

{|class="infobox" style="font-size: 90%; border: 1px solid #999; float: right; margin-left: 1em; width: 240px;" |- style="background:#f5f5f5;" ! colspan="2" | Race/Ethnicity (2010) |- | White || style="text-align: center;" |72.4% |- | Black/African American || style="text-align: center;" |12.6% |- | Asian || style="text-align: center;" |4.8% |- | American Indian and Alaska Native || style="text-align: center;" |0.9% |- | Native Hawaiian and Pacific Islander || style="text-align: center;" |0.2% |- | Other || style="text-align: center;" |6.2% |- | Two or more races || style="text-align: center;" | 2.9% |- | Hispanic/Latino (of any race) || style="text-align: center;" |16.3% |}

The U.S. Census Bureau estimates the country's population now to be }}, including an estimated 11.2 million illegal immigrants. The U.S. population almost quadrupled during the 20th century, from about 76 million in 1900. The third most populous nation in the world, after China and India, the United States is the only industrialized nation in which large population increases are projected. Even with a birth rate of 13.82 per 1,000, 30% below the world average, its population growth rate is positive at 1%, significantly higher than those of many developed nations. In fiscal year 2010, over 1 million immigrants (most of whom entered through family reunification) were granted legal residence. Mexico has been the leading source of new residents for over two decades; since 1998, China, India, and the Philippines have been in the top four sending countries every year.

The United States has a very diverse population—thirty-one ancestry groups have more than one million members. White Americans are the largest racial group; German Americans, Irish Americans, and English Americans constitute three of the country's four largest ancestry groups. African Americans are the nation's largest racial minority and third largest ancestry group. Asian Americans are the country's second largest racial minority; the two largest Asian American ethnic groups are Chinese Americans and Filipino Americans. In 2010, the U.S. population included an estimated 5.2 million people with some American Indian or Alaska Native ancestry (2.9 million exclusively of such ancestry) and 1.2 million with some native Hawaiian or Pacific island ancestry (0.5 million exclusively). The census counted more than 19 million people of "Some Other Race" who were "unable to identify with any" of its five official race categories in 2010.

The population growth of Hispanic and Latino Americans (the terms are officially interchangeable) is a major demographic trend. The 50.5 million Americans of Hispanic descent are identified as sharing a distinct "ethnicity" by the Census Bureau; 64% of Hispanic Americans are of Mexican descent. Between 2000 and 2010, the country's Hispanic population increased 43% while the non-Hispanic population rose just 4.9%. Much of this growth is from immigration; as of 2007, 12.6% of the U.S. population was foreign-born, with 54% of that figure born in Latin America. Fertility is also a factor; the average Hispanic woman gives birth to 3.0 children in her lifetime, compared to 2.2 for non-Hispanic black women and 1.8 for non-Hispanic white women (below the replacement rate of 2.1). Minorities (as defined by the Census Bureau, all those beside non-Hispanic, non-multiracial whites) constitute 34% of the population, and are projected to constitute the majority by 2042.

About 82% of Americans live in urban areas (including suburbs); about half of those reside in cities with populations over 50,000. In 2008, 273 incorporated places had populations over 100,000, nine cities had more than 1 million residents, and four global cities had over 2 million (New York City, Los Angeles, Chicago, and Houston). There are fifty-two metropolitan areas with populations greater than 1 million. Of the fifty fastest-growing metro areas, forty-seven are in the West or South. The metro areas of Dallas, Houston, Atlanta, and Phoenix all grew by more than a million people between 2000 and 2008.

Language

{|class="infobox" style="font-size: 90%; border: 1px solid #999; float: right; margin-left: 1em; width: 200px;" |- style="background:#f5f5f5;" !colspan="2"|Languages (2007) |- |English (only)||style="text-align: center;"|225.5 million |- |Spanish, incl. Creole||style="text-align: center;"|34.5 million |- |Chinese||style="text-align: center;"|2.5 million |- |French, incl. Creole||style="text-align: center;"|2.0 million |- |Tagalog||style="text-align: center;"|1.5 million |- |Vietnamese||style="text-align: center;"|1.2 million |- |German||style="text-align: center;"|1.1 million |- |Korean||style="text-align: center;"|1.1 million |}

English is the de facto national language. Although there is no official language at the federal level, some laws—such as U.S. naturalization requirements—standardize English. In 2007, about 226 million, or 80% of the population aged five years and older, spoke only English at home. Spanish, spoken by 12% of the population at home, is the second most common language and the most widely taught second language. Some Americans advocate making English the country's official language, as it is in at least twenty-eight states. Both Hawaiian and English are official languages in Hawaii by state law.

While neither has an official language, New Mexico has laws providing for the use of both English and Spanish, as Louisiana does for English and French. Other states, such as California, mandate the publication of Spanish versions of certain government documents including court forms. Many jurisdictions with large numbers of non-English speakers produce government materials, especially voting information, in the most commonly spoken languages in those jurisdictions. Several insular territories grant official recognition to their native languages, along with English: Samoan and Chamorro are recognized by American Samoa and Guam, respectively; Carolinian and Chamorro are recognized by the Northern Mariana Islands; Spanish is an official language of Puerto Rico.

Religion

The United States is officially a secular nation; the First Amendment of the U.S. Constitution guarantees the free exercise of religion and forbids the establishment of any religious governance. In a 2002 study, 59% of Americans said that religion played a "very important role in their lives", a far higher figure than that of any other wealthy nation. According to a 2007 survey, 78.4% of adults identified themselves as Christian, down from 86.4% in 1990. Protestant denominations accounted for 51.3%, while Roman Catholicism, at 23.9%, was the largest individual denomination. The study categorizes white evangelicals, 26.3% of the population, as the country's largest religious cohort; another study estimates evangelicals of all races at 30–35%. The total reporting non-Christian religions in 2007 was 4.7%, up from 3.3% in 1990. The leading non-Christian faiths were Judaism (1.7%), Buddhism (0.7%), Islam (0.6%), Hinduism (0.4%), and Unitarian Universalism (0.3%). The survey also reported that 16.1% of Americans described themselves as agnostic, atheist, or simply having no religion, up from 8.2% in 1990.

Family structure

In 2007, 58% of Americans age 18 and over were married, 6% were widowed, 10% were divorced, and 25% had never been married. Women now mostly work outside the home and receive a majority of bachelor's degrees.

Same-sex marriage is a contentious issue. Some states permit civil unions or domestic partnerships in lieu of marriage. Since 2003, several states have legalized gay marriage as the result of judicial or legislative action. Meanwhile, the federal government and a majority of states define marriage as between a man and a woman and/or explicitly prohibit same-sex marriage. Public opinion on the issue has shifted from general opposition in the 1990s to a statistical deadlock as of 2011.

The U.S. teenage pregnancy rate, 79.8 per 1,000 women, is the highest among OECD nations. Abortion policy was left to the states until the Supreme Court legalized the practice in 1972. The issue remains highly controversial, with public opinion closely divided for many years. Many states ban public funding of the procedure and restrict late-term abortions, require parental notification for minors, and mandate a waiting period. While the abortion rate is falling, the abortion ratio of 241 per 1,000 live births and abortion rate of 15 per 1,000 women aged 15–44 remain higher than those of most Western nations.

Culture

The United States is a multicultural nation, home to a wide variety of ethnic groups, traditions, and values. Aside from the now small Native American and Native Hawaiian populations, nearly all Americans or their ancestors immigrated within the past five centuries. The culture held in common by most Americans—mainstream American culture—is a Western culture largely derived from the traditions of European immigrants with influences from many other sources, such as traditions brought by slaves from Africa. More recent immigration from Asia and especially Latin America has added to a cultural mix that has been described as both a homogenizing melting pot, and a heterogeneous salad bowl in which immigrants and their descendants retain distinctive cultural characteristics.

American culture is considered the most individualistic in the world. Though the American Dream, or the perception that Americans enjoy high social mobility, plays a key role in attracting immigrants, other developed nations offer greater social mobility. While the mainstream culture holds that the United States is a classless society, scholars identify significant differences between the country's social classes, affecting socialization, language, and values. The American middle and professional class has initiated many contemporary social trends such as modern feminism, environmentalism, and multiculturalism. Americans' self-images, social viewpoints, and cultural expectations are associated with their occupations to an unusually close degree. While Americans tend greatly to value socioeconomic achievement, being ordinary or average is generally seen as a positive attribute.

Popular media

The world's first commercial motion picture exhibition was given in New York City in 1894, using Thomas Edison's Kinetoscope. The next year saw the first commercial screening of a projected film, also in New York, and the United States was in the forefront of sound film's development in the following decades. Since the early 20th century, the U.S. film industry has largely been based in and around Hollywood, California. Director D. W. Griffith was central to the development of film grammar and Orson Welles's Citizen Kane (1941) is frequently cited as the greatest film of all time. American screen actors like John Wayne and Marilyn Monroe have become iconic figures, while producer/entrepreneur Walt Disney was a leader in both animated film and movie merchandising. The major film studios of Hollywood have produced the most commercially successful movies in history, such as Star Wars (1977) and Titanic (1997), and the products of Hollywood today dominate the global film industry.

Americans are the heaviest television viewers in the world, and the average viewing time continues to rise, reaching five hours a day in 2006. The four major broadcast networks are all commercial entities. Americans listen to radio programming, also largely commercialized, on average just over two-and-a-half hours a day. Aside from web portals and search engines, the most popular websites are Facebook, YouTube, Wikipedia, Blogger, eBay, and Craigslist.

The rhythmic and lyrical styles of African-American music have deeply influenced American music at large, distinguishing it from European traditions. Elements from folk idioms such as the blues and what is now known as old-time music were adopted and transformed into popular genres with global audiences. Jazz was developed by innovators such as Louis Armstrong and Duke Ellington early in the 20th century. Country music developed in the 1920s, and rhythm and blues in the 1940s. Elvis Presley and Chuck Berry were among the mid-1950s pioneers of rock and roll. In the 1960s, Bob Dylan emerged from the folk revival to become one of America's most celebrated songwriters and James Brown led the development of funk. More recent American creations include hip hop and house music. American pop stars such as Presley, Michael Jackson, and Madonna have become global celebrities.

Literature, philosophy, and the arts

In the 18th and early 19th centuries, American art and literature took most of its cues from Europe. Writers such as Nathaniel Hawthorne, Edgar Allan Poe, and Henry David Thoreau established a distinctive American literary voice by the middle of the 19th century. Mark Twain and poet Walt Whitman were major figures in the century's second half; Emily Dickinson, virtually unknown during her lifetime, is now recognized as an essential American poet. A work seen as capturing fundamental aspects of the national experience and character—such as Herman Melville's Moby-Dick (1851), Twain's The Adventures of Huckleberry Finn (1885), and F. Scott Fitzgerald's The Great Gatsby (1925)—may be dubbed the "Great American Novel".

Eleven U.S. citizens have won the Nobel Prize in Literature, most recently Toni Morrison in 1993. William Faulkner and Ernest Hemingway are often named among the most influential writers of the 20th century. Popular literary genres such as the Western and hardboiled crime fiction developed in the United States. The Beat Generation writers opened up new literary approaches, as have postmodernist authors such as John Barth, Thomas Pynchon, and Don DeLillo.

The transcendentalists, led by Thoreau and Ralph Waldo Emerson, established the first major American philosophical movement. After the Civil War, Charles Sanders Peirce and then William James and John Dewey were leaders in the development of pragmatism. In the 20th century, the work of W. V. Quine and Richard Rorty, built upon by Noam Chomsky, brought analytic philosophy to the fore of U.S. academics. John Rawls and Robert Nozick led a revival of political philosophy.

In the visual arts, the Hudson River School was a mid-19th-century movement in the tradition of European naturalism. The realist paintings of Thomas Eakins are now widely celebrated. The 1913 Armory Show in New York City, an exhibition of European modernist art, shocked the public and transformed the U.S. art scene. Georgia O'Keeffe, Marsden Hartley, and others experimented with new styles, displaying a highly individualistic sensibility. Major artistic movements such as the abstract expressionism of Jackson Pollock and Willem de Kooning and the pop art of Andy Warhol and Roy Lichtenstein developed largely in the United States. The tide of modernism and then postmodernism has brought fame to American architects such as Frank Lloyd Wright, Philip Johnson, and Frank Gehry. One of the first major promoters of American theater was impresario P. T. Barnum, who began operating a lower Manhattan entertainment complex in 1841. The team of Harrigan and Hart produced a series of popular musical comedies in New York starting in the late 1870s. In the 20th century, the modern musical form emerged on Broadway; the songs of musical theater composers such as Irving Berlin, Cole Porter, and Stephen Sondheim have become pop standards. Playwright Eugene O'Neill won the Nobel literature prize in 1936; other acclaimed U.S. dramatists include multiple Pulitzer Prize winners Tennessee Williams, Edward Albee, and August Wilson.

Though little known at the time, Charles Ives's work of the 1910s established him as the first major U.S. composer in the classical tradition, while experimentalists such as Henry Cowell and John Cage created a distinctive American approach to classical composition. Aaron Copland and George Gershwin developed a new synthesis of popular and classical music. Choreographers Isadora Duncan and Martha Graham helped create modern dance, while George Balanchine and Jerome Robbins were leaders in 20th century ballet. Americans have long been important in the modern artistic medium of photography, with major photographers including Alfred Stieglitz, Edward Steichen, and Ansel Adams. The newspaper comic strip and the comic book are both U.S. innovations. Superman, the quintessential comic book superhero, has become an American icon.

Food

Mainstream American cuisine is similar to that in other Western countries. Wheat is the primary cereal grain. Traditional American cuisine uses indigenous ingredients, such as turkey, venison, potatoes, sweet potatoes, corn, squash, and maple syrup, which were consumed by Native Americans and early European settlers. Slow-cooked pork and beef barbecue, crab cakes, potato chips, and chocolate chip cookies are distinctively American foods. Soul food, developed by African slaves, is popular around the South and among many African Americans elsewhere. Syncretic cuisines such as Louisiana creole, Cajun, and Tex-Mex are regionally important.

Characteristic dishes such as apple pie, fried chicken, pizza, hamburgers, and hot dogs derive from the recipes of various immigrants. French fries, Mexican dishes such as burritos and tacos, and pasta dishes freely adapted from Italian sources are widely consumed. Americans generally prefer coffee to tea. Marketing by U.S. industries is largely responsible for making orange juice and milk ubiquitous breakfast beverages.

The American fast food industry, the world's largest, pioneered the drive-through format in the 1930s. Fast food consumption has sparked health concerns. During the 1980s and 1990s, Americans' caloric intake rose 24%; frequent dining at fast food outlets is associated with what public health officials call the American "obesity epidemic". Highly sweetened soft drinks are widely popular, and sugared beverages account for 9% of American caloric intake.

Sports

Baseball has been regarded as the national sport since the late 19th century, while American football is now by several measures the most popular spectator sport. Basketball and ice hockey are the country's next two leading professional team sports. College football and basketball attract large audiences. Boxing and horse racing were once the most watched individual sports, but they have been eclipsed by golf and auto racing, particularly NASCAR. Soccer is played widely at the youth and amateur levels. Tennis and many outdoor sports are popular as well.

While most major U.S. sports have evolved out of European practices, basketball, volleyball, skateboarding, snowboarding, and cheerleading are American inventions. Lacrosse and surfing arose from Native American and Native Hawaiian activities that predate Western contact. Eight Olympic Games have taken place in the United States. The United States has won 2,301 medals at the Summer Olympic Games, more than any other country, and 253 in the Winter Olympic Games, the second most.

Measurement systems

The country retains United States customary units, constituted largely by British imperial units such as miles, yards, and degrees Fahrenheit. Distinct units include the U.S. gallon and U.S. pint volume measurements. The United States is one of only three countries that have not adopted the International System of Units. However, metric units are increasingly used in science, medicine, and many industrial fields.

See also

International rankings of the United States

List of Americans

List of places in the United States

List of U.S. state portals

References

External links

;Government

Official U.S. Government Web Portal Gateway to government sites

House Official site of the United States House of Representatives

Senate Official site of the United States Senate

White House Official site of the President of the United States

[ Supreme Court] Official site of the Supreme Court of the United States ;Overviews and Data

InfoUSA Portal to U.S. Information Agency resources

Library of Congress Official site of the U.S. Library of Congress

Demographic Highlights Statistics from the Population Reference Bureau

The 50 States of the U.S.A. Collected informational links for each state

United States travel guide from Wikitravel

United States Encyclopædia Britannica entry

U.S. Census Housing and Economic Statistics Wide-ranging data from the U.S. Census Bureau

U.S. Citizenship and Immigration Services Official government site

State Fact Sheets Population, employment, income, and farm data from the U.S. Economic Research Service

State Energy Profiles Economic, environmental, and energy data for each state from the U.S. Energy Information Administration

;History

Historical Documents Collected by the National Center for Public Policy Research

U.S. National Mottos: History and Constitutionality Analysis by the Ontario Consultants on Religious Tolerance

USA Collected links to historical data

;Maps

National Atlas of the United States Official maps from the U.S. Department of the Interior

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{{infobox military unit |unit name

United States Navy |image |caption United States Navy portal |dates October 13, 1775 – 1790, 1797–present |country United States |allegiance |branch |type Navy |size 333,642 active duty personnel286 ships3,700+ aircraft11 Aircraft carriers9 Amphibious assault ships9 Amphibious transport docks12 Dock landing ships 22 Cruisers 60 Destroyers 28 Frigates 75 Submarines |command_structure Department of Defense Department of the Navy |garrison The Pentagon |garrison_label Headquarters |nickname |motto"Honor, Courage, Commitment" "Non sibi sed patriae"'' (Not self but country) (unofficial) |patron |colors Blue, Gold |colors_label Colors |march Anchors Aweigh |mascot |equipment |equipment_label |battles |anniversaries |decorations |battle_honours |commander1 Hon. Ray Mabus |commander1_label Secretary |commander2 ADM Gary Roughead |commander2_label Chief of Naval Operations |commander3 ADM Mark E. Ferguson III |commander3_label Vice Chief of Naval Operations |commander4 MCPON Rick D. West |commander4_label Master Chief Petty Officer |notable_commanders |identification_symbol |identification_symbol_label Naval Jack |identification_symbol_2 |identification_symbol_2_label |identification_symbol_3 |identification_symbol_3_label |identification_symbol_4 |identification_symbol_4_label |aircraft_attackF/A-18A/B/C/D, F/A-18E/F |aircraft_bomber |aircraft_electronicE-2C, EP-3E, E-6, EA-6B, EA-18G |aircraft_fighterF/A-18A/B/C/D, F/A-18E/F |aircraft_helicopter UH-1, SH-3, CH-53D, MH-53E, SH-60B/F, HH-60H, MH-60R/S |aircraft_interceptor |aircraft_patrolP-3, P-8 |aircraft_reconRQ-2 |aircraft_trainerF-5, F-16N, T-2C, T-6, T-34, T-39, T-44, T-45, TH-57 |aircraft_transportC-2, C-9, C-12, C-20, C-40, C-130 }}

The United States Navy (USN) is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S. Navy also has the world's largest carrier fleet, with 11 in service, one under construction (two planned), and one in reserve. The service had 328,516 personnel on active duty and 101,689 in the Navy Reserve in January 2011. It operates 286 ships in active service and more than 3,700 aircraft.

The Navy traces its origins to the Continental Navy, which was established during the American Revolutionary War and was essentially disbanded as a separate entity shortly thereafter. The United States Constitution provided the legal basis for a military force by giving Congress the power "to provide and maintain a navy".

Depredations against U.S. shipping by Barbary Coast pirates in the Mediterranean Sea spurred Congress to employ this power by passing the Naval Act of 1794 ordering the construction and manning of six frigates. These ships were used to end most pirate activity off the Barbary Coast. In the 20th century American blue-water navy capability was demonstrated by the 1907–1909 world tour of the Great White Fleet.

The 21st century United States Navy maintains a sizable global presence, deploying in such areas as East Asia, the Mediterranean, and the Middle East. It is a blue-water navy with the ability to project force onto the littoral regions of the world, engage in forward areas during peacetime, and rapidly respond to regional crises, making it an active player in U.S. foreign and defense policy.

The Navy is administratively managed by the Department of the Navy, which is headed by the civilian Secretary of the Navy. The Department of the Navy is itself a division of the Department of Defense, which is headed by the Secretary of Defense. Traditionally, the highest ranking naval officer is the Chief of Naval Operations, a position currently held by Admiral Gary Roughead, however two naval officers currently outrank him. The highest ranking naval officer is the Chairman of the Joint Chiefs of Staff, Admiral Michael Mullen and the second highest ranking is the Vice Chairman of the Joint Chiefs of Staff, Admiral James Winnefeld.

Mission

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From the New Recruits Handbook:

The United States Navy serves as a seaborne branch of the Military of the United States. prescribes the Navy's three primary areas of responsibility:

"The preparation of naval forces necessary for the effective prosecution of war"

"The maintenance of naval aviation, including land-based naval aviation, air transport essential for naval operations and all air weapons and air techniques involved in the operations and activities of the Navy"

"The development of aircraft, weapons, tactics, technique, organization, and equipment of naval combat and service elements".

U.S. Navy training manuals state the mission of the U.S armed forces is "to prepare and conduct prompt and sustained combat operations in support of the national interest". As part of that establishment, the U.S. Navy's functions comprise sea control, power projection and nuclear deterrence, in addition to "sealift" duties.

History

Origins

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In the early stages of the American Revolutionary War, the establishment of an official navy was an issue of debate among the members of the Continental Congress. Supporters argued that a navy would protect shipping, defend the coast, and make it easier to seek out support from foreign countries. Detractors countered that challenging the British Royal Navy, then the world's preeminent naval power, was a foolish undertaking.

Commander in Chief George Washington commissioned seven ocean-going cruisers to interdict British supply ships, and reported the captures to the Congress. This effectively ended the debate in Congress as to whether or not to "provoke" the British by establishing a Navy as Washington's ships had already captured British ships, somewhat a provocation.

While Congress deliberated, it received word that two unarmed British supply ships from England were heading towards Quebec without escort. A plan was drawn up to intercept the ships—however, the armed vessels to be used were owned not by Congress, but by individual colonies. Of greater significance then was an additional plan to equip two ships that would operate under the direct authority of Congress to capture British supply ships. This was not carried out until 13 October 1775, when George Washington announced that he had taken command of three armed schooners under Continental authority to intercept any British supply ships near Massachusetts. With the revelation that vessels were already sailing under Continental control, the decision to add two more was made easier; the resolution was adopted and 13 October would later become known as the U.S. Navy's official birthday.

The Continental Navy achieved mixed results; it was successful in a number of engagements and raided many British merchant vessels, but it lost 24 of its vessels and at one point was reduced to two in active service. As Congress turned its attention after the conflict towards securing the western border of the new United States, a standing navy was considered to be dispensable because of its high operating costs and its limited number of roles.

From reestablishment to the Civil War

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The United States would be without a navy for nearly a decade—a state of affairs that exposed its merchant ships to a series of attacks by Barbary pirates. The sole armed maritime presence between 1790 and the launching of the U.S. Navy's first warships in 1797 was the U.S. Revenue Cutter Service (USRCS), the primary predecessor of the U.S. Coast Guard. Although USRCS Cutters conducted operations against these pirates, the depredations far outstripped the abilities of the USRCS and Congress ordered the construction and manning of six frigates on 27 March 1794; three years later the first three were welcomed into service: the USS United States, USS Constellation and USS Constitution.

Following an undeclared Quasi-War with France, the U.S. Navy saw substantial action in the War of 1812, where it was victorious in numerous single-ship duels with the Royal Navy. The Navy drove all significant British forces off of Lake Erie and Lake Champlain and prevented them from becoming British controlled zones of conflict. Despite this, the U.S. Navy was unable to prevent the British from blockading American ports and landing troops on American soil. After the war, the U.S. Navy again focused its attention on protecting American shipping assets, sending squadrons to the Caribbean, the Mediterranean, South America, Africa, and the Pacific.

During the Mexican-American War the U.S. Navy contributed by instituting blockades of Mexican ports, capturing or burning the Mexican fleet in the Gulf of California and capturing all major cities in Baja California peninsula—later returned. In 1846-1848 the navy successfully used the Pacific Squadron under Commodore (Rear Admiral) Robert Stockton and its marines and blue-jackets to facilitate the capture of California with large scale land operations coordinated with the local militia organized in the California Battalion. The navy conducted the U.S. military's first large-scale amphibious joint operation by successfully landing 12,000 army troops with their equipment in one day at Veracruz, Mexico. When larger guns were needed to bombard Veracruz Navy volunteers landed large navy guns and manned them in the successful bombardment of the city and its surrender. This successful landing and capture of Veracruz eventually opening the way for the capture of Mexico City and the end of the war. The United States Navy established itself as a player in American foreign policy through the actions of Commodore Matthew Perry in Japan, which resulted in the Convention of Kanagawa in 1854.

Naval power would play a significant role during the American Civil War, where the Union had a distinct advantage over the Confederacy on the seas. A Union blockade on shipping handicapped the Southern effort throughout the conflict. The two American navies would help usher in a new era in world naval history by putting ironclad warships into combat for the first time. The Battle of Hampton Roads in 1862, which pitted USS Monitor against CSS Virginia, became the first engagement between two steam-powered ironclads. Soon after the war, however, the U.S. Navy's fleet slipped into obsolescence because of neglect.

20th century

A modernization program beginning in the 1880s brought the U.S. in line with the navies of countries such as Britain and Germany. In 1907, most of the Navy's battleships, with several support vessels, dubbed the Great White Fleet, were showcased in a 14-month circumnavigation of the world. Ordered by President Theodore Roosevelt, it was a mission designed to demonstrate the Navy's capability to extend to the global theater.

The Navy saw little action during World War I, but nevertheless the strength of the United States Navy grew under an ambitious ship building program associated with the Naval Act of 1916. Naval construction, especially of battleships was later limited by the Washington Naval Conference of 1921-22, however, construction of aircraft carriers continued, accelerating after the New Deal which provided funding for the construction of the and . By 1936, with the completion of the , the U.S. Navy possessed a carrier fleet of 165,000 tonnes displacement, although this figure was nominally recorded as 135,000 tonnes to comply with treaty limitations.

World War II

The U.S. Navy grew into a formidable force in the years prior to World War II, with battleship production being restarted in 1937, commencing with the . Though ultimately unsuccessful, Japan attempted to allay this strategic threat with the 1941 surprise attack on Pearl Harbor. Following American entry into the war, the U.S. Navy grew tremendously as the United States was faced with a two-front war on the seas. It achieved notable acclaim in the Pacific Theater, where it was instrumental to the Allies' successful "island hopping" campaign. The U.S. Navy participated in many significant battles, including the Battle of the Coral Sea, the Battle of Midway, the Battle of the Philippine Sea, the Battle of Leyte Gulf, and the Battle of Okinawa. By 1943, the Navy's size was larger than the combined fleets of all the other combatant nations in World War II. By war's end in 1945, the United States Navy had added hundreds of new ships, including 18 aircraft carriers and 8 battleships, and had over 70% of the world's total numbers and total tonnage of naval vessels of 1,000 tons or greater. At its peak, the U.S. Navy was operating 6,768 ships on V-J Day in August 1945.

Doctrine had significantly shifted by the end of the war. The United States Navy had followed in the footsteps of the navies of Great Britain and Germany which favored concentrated groups of battleships as their main offensive naval weapons. The development of the aircraft carrier and its devastating utilization by the Japanese against the U.S. at Pearl Harbor however shifted U.S. thinking. The Pearl Harbor attack destroyed or took out of action a significant number of U.S.N. battleships. This placed much of the burden of retaliating against the Japanese on the small number of aircraft carriers.

The potential for armed conflict with the Soviet Union during the Cold War pushed the U.S. Navy to continue its technological advancement by developing new weapons systems, ships, and aircraft. United States naval strategy changed to that of forward deployment in support of U.S. allies with an emphasis on carrier battle groups.

The Navy was a major participant in the Vietnam War, blockaded Cuba during the Cuban Missile Crisis, and, through the use of ballistic missile submarines, became an important aspect of the United States' nuclear strategic deterrence policy. The United States Navy conducted various combat operations in the Persian Gulf against Iran in 1987 and 1988, most notably Operation Praying Mantis. The Navy was extensively involved in Operation Urgent Fury, Operation Desert Shield, Operation Desert Storm, Operation Deliberate Force, Operation Allied Force, Operation Desert Fox and Operation Southern Watch.

The U.S. Navy has also been involved in Search and Rescue/Search and Salvage operations, some times in conjunction with vessels of other countries as well as with U.S. Coast Guard ships. Two examples are the 1966 Palomares B-52 crash incident and search for the nuclear bombs, and the Task Force 71 of the Seventh Fleet operation in search for Korean Air Lines Flight 007 shot down by the Soviets on Sept. 1, 1983.

21st century

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The United States Navy continues to be a major support to U.S. interests in the 21st century. Since the end of the Cold War, it has shifted its focus from preparations for large-scale war with the Soviet Union to special operations and strike missions in regional conflicts. The Navy participated in Operation Enduring Freedom, Operation Iraqi Freedom, and is a major participant in the ongoing War on Terror, largely in this capacity. Development continues on new ships and weapons, including the Gerald R. Ford class aircraft carrier and the Littoral combat ship. Because of its size, weapons technology, and ability to project force far from U.S. shores, the current U.S. Navy remains a potent asset for the United States Commander-in-Chief (the President of the United States).

In 2007, the U.S. Navy joined with the U.S. Marine Corps and U.S. Coast Guard to adopt a new maritime strategy called A Cooperative Strategy for 21st Century Seapower that raises the notion of prevention of war to the same philosophical level as the conduct of war. The strategy was presented by the Chief of Naval Operations, the Commandant of the Marine Corps and Commandant of the Coast Guard at the International Sea power Symposium in Newport, R.I. on 17 October 2007. The strategy recognized the economic links of the global system and how any disruption due to regional crises—man made or natural—can adversely impact the U.S. economy and quality of life. This new strategy charts a course for the Navy, Coast Guard and Marine Corps to work collectively with each other and international partners to prevent these crises from occurring or reacting quickly should one occur to prevent negative impacts on the United States.

In 2010, Chief of Naval Operations, Admiral Gary Roughead noted that demands on the Navy have grown as the fleet has shrunk and that in the face of declining budgets in the future the US Navy must rely even more on international partnerships.

Organization

The Navy falls under the administration of the Department of the Navy, under civilian leadership of the Secretary of the Navy (SECNAV). The most senior naval officer is the Chief of Naval Operations (CNO), a four-star admiral who is immediately under and reports to the Secretary of the Navy. At the same time, the Chief of Naval Operations is one of the Joint Chiefs of Staff, which is the second-highest deliberatory body of the armed forces after the United States National Security Council, although it only plays an advisory role to the President and does not nominally form part of the chain of command. The Secretary of the Navy and Chief of Naval Operations are responsible for organizing, recruiting, training, and equipping the Navy so that it is ready for operation under the command of the Unified Combatant Commanders.

Operating forces

There are nine components in the operating forces of the U.S. Navy: the United States Fleet Forces Command, United States Pacific Fleet, United States Naval Forces Central Command, United States Naval Forces Europe, Naval Network Warfare Command, Navy Reserve, United States Naval Special Warfare Command, Operational Test and Evaluation Force, and Military Sealift Command. Fleet Forces Command controls a number of unique capabilities, including Military Sealift Command, Naval Expeditionary Combat Command, and Navy Cyber Forces.

The United States Navy has seven active numbered fleets — Second, Third, Fifth, Sixth, Seventh Fleet and Tenth Fleets are each led by a three-star vice admiral, and the Fourth Fleet is led by a rear admiral. These seven fleets are further grouped under Fleet Forces Command (the former Atlantic Fleet), Pacific Fleet, Naval Forces Europe-Africa, and Naval Forces Central Command, whose commander also doubles as Commander Fifth Fleet; the first three commands being led by four-star full admirals. The United States First Fleet existed after the Second World War from 1947, but it was redesignated Third Fleet in early 1973. In early 2008, the Navy reactivated the United States Fourth Fleet to control operations in the area controlled by Southern Command, which consists of US assets in and around Central and South America.

Shore establishments

Shore establishments exist to support the mission of the fleet through the use of facilities on land. Among the commands of the shore establishment, as of April 2011, are the Naval Education and Training Command, the Naval Meteorology and Oceanography Command, the Space and Naval Warfare Systems Command, the Naval Facilities Engineering Command, the Naval Supply Systems Command, the Naval Air Systems Command, the Naval Sea Systems Command, the Bureau of Medicine and Surgery, the Bureau of Naval Personnel, the United States Naval Academy, the Naval Safety Center, the Naval Strike and Air Warfare Center, and the United States Naval Observatory. Official Navy websites list the Office of the Chief of Naval Operations and the Chief of Naval Operations (CNO) as part of the shore establishment, but these two entities effectively sit superior to the other organizations, playing a coordinating role.

Relationships with other service branches

United States Marine Corps

In 1834, the Marines came under the Department of the Navy. Historically, the United States Navy has had a unique relationship with the United States Marine Corps (USMC), partly because they both specialize in seaborne operations. Together the Navy and Marine Corps form the Department of the Navy and report to the Secretary of the Navy. However, the USMC is considered to be a distinct, separate service branch with its own uniformed service chief - the Commandant of the Marine Corps (CMC), a four star general.

The Navy and Marine Corps have a distinct relationship, the USMC depends on the Navy for religious support (i.e. chaplains) and medical support (i.e., dentists, medical doctors, medics known as "Corpsmen" and medical service staff); thus officers and enlisted sailors from the Navy fulfill these roles. When attached to Marine Corps units deployed to an operational environment they generally wear Marine camouflage uniforms, but otherwise they wear Navy dress uniforms unless they opt to conform to USMC grooming standards (appearance).

In the operational environment, as an expeditionary force specializing in amphibious operations, Marines often embark on Navy ships in order to conduct operations from beyond territorial waters. Marine units deploying as part of a Marine Air-Ground Task Force (MAGTF) operate under the command of the existing Marine chain of command. Although Marine units routinely operate from amphibious assault ships the relationship has evolved over the years much as the "CAG" (Commander of the Carrier Air Group/Wing) does not work for the carrier Commanding Officer (CO), but coordinates with the ship's CO and staff. Some Marine aviation squadrons, usually fixed-wing assigned to Carrier Air Wings (CVW) train and operate alongside Navy squadrons, flying similar missions and often flying sorties together under the cognizance of the "CAG". Aviation is where the Navy and Marine share the most common ground, since aircrews are guided in their use of aircraft by standard procedures outlined in series of publications known as NATOPS manuals.

United States Coast Guard

Although the Posse Comitatus Act, which prevents federal military personnel from acting in a law enforcement capacity, applies only to the Army and Air Force, Department of Defense rules effectively require the Navy and Marine Corps to act as if Posse Comitatus did apply, preventing them from enforcing Federal law. The United States Coast Guard fulfills this law enforcement role in naval operations. It provides Law Enforcement Detachments (LEDETs) to Navy vessels, where they perform arrests and other law enforcement duties during Navy boarding and interdiction missions. In times of war, or when directed by the President, the Coast Guard operates as a service in the Navy and is subject to the orders of the Secretary of the Navy until it is transferred back to the Department of Homeland Security. At other times, Coast Guard Port Security Units are sent overseas to guard the security of ports and other assets. The Coast Guard also jointly staffs the Navy's Naval Coastal Warfare Groups and Squadrons (the latter of which were known as Harbor Defense Commands until late-2004), which oversee defense efforts in foreign littoral combat and inshore areas. Additionally, Coast Guard and Navy vessels sometimes operate together in search and rescue operations.

Personnel

The United States Navy has nearly 500,000 personnel, approximately a quarter of whom are in ready reserve. Of those on active duty, more than eighty percent are enlisted sailors, and around fifteen percent are commissioned officers; the rest are midshipmen of the United States Naval Academy and midshipmen of the Naval Reserve Officer Training Corps at over 180 universities around the country and officer candidates at the Navy's Officer Candidate School.

Sailors prove they have mastered skills and deserve responsibilities by completing Personnel Qualification Standards (PQS) tasks and examinations. Among the most important is the "warfare qualification", which denotes a journeyman level of capability in Surface Warfare, Aviation Warfare, Naval Aircrew, Special Warfare, Submarine Warfare or Expeditionary Warfare. Many qualifications are denoted on a sailor's uniform with U.S. Navy badges and insignia.

Commissioned officer

Commissioned officers in the Navy have pay grades ranging from O-1 to O-10, with O-10 being the highest; those with paygrades between O-1 through O-4 are considered junior officers and O-5 and O-6 as senior officers. Officers in the O-7 to O-10 range are called flag officers or "the admiralty". Promotion through O-8 is based on performance in an officer's current paygrade, which is recorded in "FITREPS" (fitness reports). Promotions to Vice Admiral (O-9) and Admiral (O-10) are based on assignment to specific positions and subject to U.S. Senate confirmation. Above the rank of Admiral is Fleet Admiral, which was awarded to only four officers in World War II and is intended to be used only during a declared war. In 1899, a special rank called Admiral of the Navy was created for Admiral George Dewey, a war hero of the Spanish-American War, with the condition that it would cease to exist upon his death. Commissioned officers originate from the United States Naval Academy, Naval Reserve Officer Training Corps (NROTC), Officer Candidate School (OCS), and a host of other commissioning programs such as the Seaman to Admiral-21 program, the Limited Duty Officer and Chief Warrant Officer Selection Programs, the United States Merchant Marine Academy, or receive direct commissions via Officer Development School (ODS) or from its reserve component, the Direct Commission Officer School (DCO School).

Commissioned officers can generally be divided into line officers and staff corps; line officers can be further split into unrestricted and restricted communities. Unrestricted Line Officers are the warfighting command element and are authorized to command ships, aviation squadrons, and special operations units. Restricted Line Officers, on the other hand, concentrate on non-combat related fields, such as engineering and maintenance; they are not qualified to command combat units. Staff Corps officers are specialists in fields that are themselves professional careers and not exclusive to the military, for example: medicine, science, law, and civil engineering.

Commissioned Officer Rank Structure of the United States Navy
Fleet Admiral (United States)>Fleet Admiral	Admiral (United States)>Admiral	Vice Admiral (United States)>Vice Admiral	Rear Admiral (United States)#Rear admiral>Rear Admiral	Rear Admiral (United States)#Rear admiral>Rear Admiral (lower half)
!Special	!O-10	!O-9	!O-8	!O-7
!FADM	!ADM	!VADM	!RADM	!RDML

Captain (United States)>Captain	Commander (United States)>Commander	Lieutenant Commander (United States)>Lieutenant Commander	!Lieutenant	Lieutenant (junior grade)>Lieutenant(junior grade)	Ensign (rank)#United States>Ensign
!O-6	!O-5	!O-4	!O-3	!O-2	!O-1
!CAPT	!CDR	!LCDR	!LT	!LTJG	!ENS

Chief Warrant Officer

Chief Warrant Officer (CWO) pay grades range from W-2 to the highest rank of W-5. United States Navy CWOs are officers whose role is to provide leadership and skills for the most difficult and demanding operations in a particular technical specialty. They occupy a niche that is not as well served by the line officer community, who tend to have a broader focus. CWOs come from the senior non-commissioned officer ranks of the enlisted and receive their commission after completing the Chief Warrant Officer Program. They typically become CWOs in specialties that are most related to their previous enlisted rating. Like Staff Corps officers, CWOs wear special insignia above the rank devices on their shoulder boards and sleeves to indicate their field of expertise.

Commissioned Warrant Officer Rank Structure of the United States Navy
Warrant Officer (United States)>Chief Warrant Officer Five	Warrant Officer (United States)>Chief Warrant Officer Four	Warrant Officer (United States)>Chief Warrant Officer Three	Warrant Officer (United States)>Chief Warrant Officer Two
!W-5	!W-4	!W-3	!W-2

Enlisted sailors

Enlisted members of the Navy have pay grades from E-1 to E-9, with E-9 being the highest. All enlisted sailors with paygrades of E-4 and higher are considered Petty Officers while those at E-7 and higher are further named Chief Petty Officers. Those who demonstrate superior performance are given an increase in paygrade; the official Navy term is to be advanced. Two notable advancements are from Seaman to Petty Officer Third Class (E-3 to E-4) and from Petty Officer First Class to Chief Petty Officer (E-6 to E-7). Advancement to Chief Petty Officer is especially significant and is marked by a special induction ceremony.

Enlisted members are said to be "rated", meaning that they possess a rating, or occupational specialty. Members of grades E-1 to E-3 can become "strikers", meaning they have rating designations like Petty Officer (example: a BM3 is a Petty Officer Third Class rated as a Boatswain's Mate; BMSN is a Seaman designated as a Boatswain's Mate striker), but the striker is doing on the job training to become a rated petty officer rather than attending a school to become rated. There are more than 50 ratings covering a broad range of skills and subspecialties. However most sailors in today's navy with grades E-1 through E-6 obtain their rating through its respective "A" school. An "A" school is a rating specific school where sailors are trained as experts in their field. Upon completion of their training they are considered "Rated", regardless of their pay-grade.

For example, SA SMITH, MARY, would be considered a Seaman Apprentice. Prior to her rank of SA a rating would be placed. Therefore, her entire title would be ITSA SMITH, MARY. IT indicating that she is an Information Systems Technician. As for ENFN THOMPSON, JOHN. EN specifying that he is an Engineman and FN as Fireman.

Non-Commissioned Officer and Enlisted Rate Structure of the United States Navy
!Master Chief Petty Officer of the Navy	Master Chief Petty Officer>Fleet/Force Master Chief Petty Officer	!Command Master Chief Petty Officer	!Master Chief Petty Officer	!Senior Chief Petty Officer	!Chief Petty Officer
E-9	!E-8	!E-7

!Petty Officer First Class	!Petty Officer Second Class	!Petty Officer Third Class	!Seaman	!Seaman Apprentice	!Seaman Recruit
!E-6	!E-5	!E-4	!E-3	!E-2	!E-1

Uniforms and appearance

The uniforms of the United States Navy are designed "to combine professionalism and naval heritage with versatility, safety, and comfort". The Navy currently incorporates many different styles that are specific for a variety of uses and occasions. In most cases, distinctions are made to distinguish officers and enlisted men in their uniformed appearance. U.S. Navy uniforms can generally be divided into three categories: dress uniforms, service uniforms, and working uniforms.

Dress uniforms are worn during military-related formal occasions, such as ceremonies and other official functions. Many types of dress uniforms are used in the Navy with the full range of formal requirements represented. Service dress is the least formal dress uniform, full dress is one step higher in formality, and mess dress is the most formal dress available.

Service uniforms are designed for daily wear and are most often worn in office or classroom-type settings, as well as other occasions in which physical activity is at a minimum. The most visible distinction between officers and enlisted personnel are the color of the service uniform. Only officers and chief petty officers are authorized to wear Service Khaki or Service White; all other personnel must wear the Navy Service Uniform (which will eventually replace Winter Blue and Summer White).

Working uniforms prioritize comfort and safety first and thus are the most utilitarian of the Navy uniforms. They are intended for use in underway ships and in occasions that involve dirty, physical labor. Many working uniforms are variations of the service uniforms except with less formal requirements. This category includes Navy coveralls, which are authorized to be worn by members of all ranks.

Recently, the Navy completed a project named "Task Force Uniform" to streamline Navy uniforms. Among the changes are that enlisted personnel from Seaman Recruit to Petty Officer First Class (E1–E6) will have one year-round service uniform instead of winter blues and summer whites. All personnel from Seaman Recruit to Admiral will also have new working uniforms dubbed Navy Working Uniform (NWU) to replace the wash khakis, coveralls, utilities, and aviation working greens currently in use. The uniform is a digital patterned camouflage in predominantly haze gray and blue hues.

Grooming for both male and female sailors is regulated to a high degree, with exact standards in regards to hair, facial hair, use of cosmetics, and jewelry. New male recruits are given the military crew cut and are prohibited from having hair longer than four inches (102 mm) while in the service. Men are required to be clean shaven at all times, although mustaches are allowed. Women do not have a hair length regulation, however hair cannot fall past the bottom edge of the uniform collar and the style of hair is strictly controlled. Multicolored hair, body piercing, and tattoos on the head, neck, and hands are banned for both sexes.

Bases

The size, complexity, and international presence of the United States Navy require a large number of navy installations to support its operations. While the majority of bases are located inside the United States itself, the Navy maintains a significant number of facilities abroad, either in U.S.-controlled territories or in foreign countries under a Status of Forces Agreement (SOFA).

Eastern United States

The second largest concentration of installations is in Hampton Roads, Virginia, where the Navy occupies over 36,000 acres (146 km²) of land. Located in Hampton Roads are NS Norfolk, homeport of the Atlantic Fleet, NAS Oceana, a Master Jet Base, Naval Amphibious Base Little Creek, as well as a number of Navy and commercial shipyards that service Navy vessels. The state of Florida is the location of three major bases, Naval Station Mayport, the Navy's fourth largest, in Jacksonville, Florida, Naval Air Station Jacksonville, a Master Air Anti-submarine Warfare base, and Naval Air Station Pensacola, home of the Naval Education and Training Command, the Naval Air Technical Training Center that provides specialty training for enlisted aviation personnel, and the primary flight training base for Navy and Marine Corps Naval Flight Officers and enlisted Naval Aircrewmen. The main U.S. Navy submarine bases on the east coast are located in Groton, Connecticut and Kings Bay, Georgia. There are also naval bases in Portsmouth, New Hampshire and Brunswick, Maine. Naval Station Great Lakes, north of Chicago, Illinois is the home of the navy's boot camp for enlisted sailors.

Western United States and Hawaii

The Navy's largest complex is China Lake, California, which covers 1.1 million acres (4,500 km²) of land, or approximately 1/3 of the United States Navy's total land holdings.

Naval Base San Diego, California is principal home to the Pacific Fleet (although the headquarters is located in Pearl Harbor). NAS North Island is located on the north side of Coronado, and is home to Headquarters for Naval Air Forces and Naval Air Force Pacific, the bulk of the Pacific Fleet's helicopter squadrons, and part of the West Coast aircraft carrier fleet. The Naval Special Warfare Center is the primary training center for SEALs, and is also located on Coronado. The other major collection of naval bases on the west coast is in Puget Sound, Washington. Among them, Naval Station Everett is one of the newer bases and the Navy states that it is its most modern facility. NAS Fallon, Nevada serves as the primary training ground for Navy Strike aircrews, and is home to the Naval Strike Air Warfare Center. Master Jet Bases are also located at NAS Lemoore, California and NAS Whidbey Island, Washington, while the carrier-based airborne early warning aircraft community and major air test activities are located at NAS Point Mugu, California. The naval presence in Hawaii is centered on Pearl Harbor Naval Base, which hosts the headquarters of the Pacific Fleet and many of its subordinate commands.

United States territories

Guam, an island strategically located in the Western Pacific Ocean, maintains a sizable U.S. Navy presence, including Naval Base Guam. The westernmost U.S. territory, it contains a natural deep water harbor capable of harboring even aircraft carriers in emergencies. Its naval air station was deactivated in 1995 and its flight activities transferred to nearby Andersen Air Force Base. Puerto Rico in the Caribbean formerly housed Roosevelt Roads Naval Station, which was shut down in 2004 shortly after the controversial closure of the live ordnance training area on nearby Vieques Island.

Foreign countries

The largest overseas base is in Yokosuka, Japan, which serves as the homeport for the Navy's largest forward-deployed fleet and is a significant base of operations in the Western Pacific. European operations revolve around facilities in Italy (Sigonella and Naples), Spain and Greece with Naples as the homeport for the Sixth Fleet and CNRE Command Naval Region Europe, which are based in Gaeta. In the Middle East, naval facilities are located almost exclusively in countries bordering the Persian Gulf, with Manama, Bahrain serving as the headquarters of U.S. Naval Forces Central Command and U.S. Fifth Fleet. Guantánamo Bay in Cuba is the oldest overseas facility and has become known in recent years as the location of a detention camp for suspected al-Qaeda operatives.

Equipment

The Navy operates 290 ships, 3,700 aircraft, 50,000 non-combat vehicles and owns 75,200 buildings on . The Navy plans to slash the dependence on fossil fuels.

Ships

The names of commissioned ships of the U.S. Navy are prefixed with the letters "USS", designating "United States Ship". Non-commissioned, civilian-manned vessels of the Navy have names that begin with "USNS", standing for "United States Naval Ship" The names of ships are officially selected by the Secretary of the Navy, often to honor important people or places. Additionally, each ship is given a letter-based hull classification symbol (for example, CVN or DDG) to indicate the vessel's type and number. All ships in the Navy inventory are placed in the Naval Vessel Register, which tracks data such as the current status of a ship, the date of its commissioning, and the date of its decommissioning. Vessels that are removed from the register prior to disposal are said to be stricken from the register. The Navy also maintains a reserve fleet of inactive vessels that are maintained for reactivation in times of need.

The U.S. Navy was one of the first to install nuclear reactors aboard naval vessels; today, nuclear energy powers all of U.S. active aircraft carriers and submarines. In the case of the Nimitz-class carrier, two naval reactors give the ship almost unlimited range and provide enough electrical energy to power a city of 100,000 people. The U.S. Navy previously operated nuclear-powered cruisers and destroyers, but all have been decommissioned.

The U.S. Navy has identified a need for 313 combat ships, but under the current plans will only be able to afford 243 to 232.

Aircraft carriers

The Navy has established a minimum requirement for 11 aircraft carriers, but will drop to 10 when the Enterprise retires before the Gerald R. Ford is ready for service. Defense Secretary Robert Gates has questioned this need.

A carrier is typically deployed along with a host of additional vessels, forming a carrier strike group. The supporting ships, which usually include three or four Aegis-equipped cruisers and destroyers, a frigate, and two attack submarines, are tasked with protecting the carrier from air, missile, sea, and undersea threats as well as providing additional strike capabilities themselves. Ready logistics support for the group is provided by a combined ammunition, oiler, and supply ship.

Enterprise class (1 in commission)

Nimitz class (10 in commission)

Gerald R. Ford class (1 under construction, at least 2 more planned)

Amphibious warfare vessels

Amphibious assault ships are the centerpieces of US amphibious warfare and fulfill the same power projection role as aircraft carriers except that their striking force comprises land forces instead of aircraft. They deliver, command, coordinate, and fully support all elements of a 2200-strong Marine Expeditionary Unit in an amphibious assault using both air and amphibious vehicles. Resembling small aircraft carriers, amphibious assault ships are capable of V/STOL, STOVL, VTOL, tiltrotor, and rotary wing aircraft operations. They also contain a well deck to support the use of Landing Craft Air Cushion (LCAC) and other amphibious assault watercraft. Recently, amphibious assault ships have begun to be deployed as the core of an expeditionary strike group, which usually consists of an additional amphibious transport dock and dock landing ship for amphibious warfare and an Aegis-equipped cruiser and destroyer, frigate, and attack submarine for group defense. Amphibious assault ships are typically named after World War II aircraft carriers.

Tarawa class (1 in commission, 4 decommissioned)

Wasp class (8 in commission)

America class (1 under construction, at least 3 more planned)

Amphibious transport docks are warships that embark, transport, and land Marines, supplies, and equipment in a supporting role during amphibious warfare missions. With a landing platform, amphibious transport docks also have the capability to serve as secondary aviation support for an expeditionary group. All amphibious transport docks can operate helicopters, LCACs, and other conventional amphibious vehicles while the newer San Antonio class of ships has been explicitly designed to operate all three elements of the Marines' "mobility triad": Expeditionary Fighting Vehicles (EFVs), the V-22 Osprey tiltrotor aircraft, and the previously mentioned LCACs. Amphibious transport docks are named for cities, except for , named for Mesa Verde National Park in Colorado, and two of the three ships named in memory of the September 11, 2001 attacks: , for the state of New York, and for Somerset County, Pennsylvania.

Austin class (4 in commission, 8 decommissioned)

San Antonio class (5 in commission, 4 under construction, 1 more planned)

The dock landing ship is a medium amphibious transport that is designed specifically to support and operate Landing Craft Air Cushions (LCACs), though it is able to operate other amphibious assault vehicles in the United States inventory as well. Dock landing ships are normally deployed as a component of an expeditionary strike group's amphibious assault contingent, operating as a secondary launch platform for LCACs. All dock landing ships are named after locations in the United States.

Whidbey Island class (8 in commission)

Harpers Ferry class (4 in commission)

Surface vessels

Cruisers are large surface combat vessels that conduct anti-air/anti-missile warfare, surface warfare, anti-submarine warfare, and strike operations independently or as members of a larger task force. Modern guided missile cruisers were developed out of a need to counter the anti-ship missile threat facing the United States Navy. This led to the development of the AN/SPY-1 phased array radar and the Standard missile with the Aegis combat system coordinating the two. Ticonderoga-class cruisers became the first to equip Aegis and were put to use primarily as anti-air and anti-missile defense in a battle force protection role. Later developments of vertical launch systems and the Tomahawk missile gave cruisers additional long-range land and sea strike capability, making them capable of both offensive and defensive battle operations. All cruisers since CG-47 have been named for famous battles with as the only exception. Previously, cruisers were either named for cities (until CG-12), former important navy figures (CG-15 to CG-35), or states (CGN-36 to CGN-41).

Ticonderoga class (22 in commission, 5 decommissioned)

Destroyers are multi-mission medium surface ships capable of sustained performance in anti-air, anti-submarine, anti-ship, and offensive strike operations. Like cruisers, the guided missile destroyers of the Navy are primarily focused on surface strikes using Tomahawk missiles and fleet defense through Aegis and the Standard missile. Destroyers additionally specialize in anti-submarine warfare and are equipped with VLA rockets and LAMPS Mk III Sea Hawk helicopters to deal with underwater threats. When deployed with a carrier strike group or expeditionary strike group, destroyers and their fellow Aegis-equipped cruisers are primarily tasked with defending the fleet while providing secondary strike capabilities. Destroyers have been named for important navy personnel and heroes since the .

Arleigh Burke class (60 in commission, one awaiting commissioning, one under construction, at least three more planned)

Modern U.S. frigates mainly perform anti-submarine warfare for carrier strike groups and amphibious expeditionary groups and provide armed escort for supply convoys and merchant shipping. They are designed to protect friendly ships against hostile submarines in low to medium threat environments, using torpedoes and LAMPS helicopters. Independently, frigates are able to conduct counterdrug missions and other maritime interception operations. The U.S. Navy expects to retire and replace its current class of frigates by 2020 as the Littoral Combat Ships are introduced into operation. As in the case of destroyers, frigates are named after naval heroes.

Oliver Hazard Perry class (19 in commission, 9 in active reserve, 23 decommissioned)

Submarines

The primary missions of submarines in the U.S. Navy are peacetime engagement, surveillance and intelligence, special operations, precision strikes, battlegroup operations, and control of the seas. The U.S. Navy operates two types: ballistic submarines and attack submarines. Ballistic submarines have only one mission: to carry and launch the nuclear Trident missile. Attack submarines have several tactical missions, including sinking ships and other subs, launching cruise missiles, gathering intelligence, and assisting in special operations. Earlier attack submarines (such as the Los Angeles class) are typically named for cities while Ohio class and later attack submarines are typically named for states. Attack submarines prior to the Los Angeles class were named for "denizens of the deep", while pre-Ohio class ballistic missile submarines were named for "famous Americans" (including foreigners with notable connections to the United States).

Ohio class ballistic missile submarines (18 in commission, with 4 converted into guided missile submarines)

Los Angeles class attack submarines (43 in commission, 2 in reserve, 17 decommissioned)

Seawolf class attack submarines (3 in commission)

Virginia class attack submarines (7 in commission, 3 under construction, 4 ordered, at least 4 more planned)

Aircraft

Carrier-based aircraft are able to strike air, sea, and land targets far from a carrier strike group while protecting friendly forces from enemy aircraft, ships, and submarines. In peacetime, aircraft's ability to project the threat of sustained attack from a mobile platform on the seas gives United States leaders significant diplomatic and crisis-management options. Aircraft additionally provide logistics support to maintain the Navy’s readiness and, through helicopters, supply platforms with which to conduct search and rescue, special operations, anti-submarine warfare (ASW), and anti-surface warfare (ASuW).

The U.S. Navy began to research the use of aircraft at sea in the 1910s, with Lt Theodore G. “Spuds” Ellyson becoming the first Naval aviator on 28 January 1911, and commissioned its first aircraft carrier, USS Langley, in 1922. United States naval aviation fully came of age in World War II, when it became clear following the Attack on Pearl Harbor, the Battle of the Coral Sea, and the Battle of Midway that aircraft carriers and the planes that they carried had replaced the battleship as the greatest weapon on the seas. Leading Navy aircraft in World War II included the Grumman F4F Wildcat, the Grumman F6F Hellcat, the Chance Vought F4U Corsair, the Douglas SBD Dauntless, and the Grumman TBF Avenger. Navy aircraft also played a significant role in conflicts during the following Cold War years, with the F-4 Phantom II and the F-14 Tomcat becoming military icons of the era. The Navy's current primary fighter and attack airplanes are the multi-mission F/A-18C/D Hornet and its newer cousin, the F/A-18E/F Super Hornet. The F-35 Lightning II is presently under development and is scheduled to replace the C and D versions of the Hornet beginning in 2012.

The Aircraft Investment Plan sees Naval aviation growing from 30 percent of current aviation forces to half of all procurement funding over the next three decades.

Weapons

Current U.S. Navy shipboard weapons systems are almost entirely focused on missiles, both as a weapon and as a threat. In an offensive role, missiles are intended to strike targets at long distances with accuracy and precision. Because they are unmanned weapons, missiles allow for attacks on heavily defended targets without risk to human pilots. Land strikes are the domain of the BGM-109 Tomahawk, which was first deployed in the 1980s and is continually being updated to increase its capabilities. For anti-ship strikes, the Navy's dedicated missile is the Harpoon missile. To defend against enemy missile attack, the Navy operates a number of systems that are all coordinated by the Aegis combat system. Medium-long range defense is provided by the Standard Missile 2, which has been deployed since the 1980s. The Standard missile doubles as the primary shipboard anti-aircraft weapon and is undergoing development for use in theater ballistic missile defense. Short range defense against missiles is provided by the Phalanx CIWS and the more recently developed RIM-162 Evolved Sea Sparrow Missile. In addition to missiles, the Navy employs Mark 46 and Mark 50 torpedoes and various types of naval mines.

Naval fixed-wing aircraft employ much of the same weapons as the United States Air Force for both air-to-air and air-to-surface combat. Air engagements are handled by the heat-seeking Sidewinder and the radar guided AMRAAM missiles along with the M61 Vulcan cannon for close range dogfighting. For surface strikes, Navy aircraft utilize a combination of missiles, smart bombs, and dumb bombs. On the list of available missiles are the Maverick, SLAM-ER and JSOW. Smart bombs include the GPS-guided JDAM and the laser-guided Paveway series. Unguided munitions such as dumb bombs and cluster bombs make up the rest of the weapons deployed by fixed-wing aircraft.

Rotary aircraft weapons are focused on anti-submarine warfare (ASW) and light to medium surface engagements. To combat submarines, helicopters use Mark 46 and Mark 50 torpedoes. Against small watercraft, they utilize Hellfire and Penguin air to surface missiles. Helicopters also employ various types of mounted anti-personnel machine guns, including the M60, M240, GAU-16/A, and GAU-17/A.

Nuclear weapons in the U.S. Navy arsenal are deployed through ballistic missile submarines and aircraft. The Ohio-class submarine carries the latest iteration of the Trident missile, a three stage, underwater launched, nuclear ICBM with MIRV capability; the current Trident II (D5) version is expected to be in service past 2020. The Navy’s other nuclear weapon is the air-deployed B61 nuclear bomb. The B61 is a thermonuclear device that can be dropped by strike aircraft such as the F/A-18 Hornet and Super Hornet at high speed from a large range of altitudes. It can be released through free-fall or parachute and can be set to detonate in the air or on the ground.

Naval Jack

The current naval jack of the United States is the First Navy Jack, traditionally regarded as having been used during the American Revolutionary War. On 31 May 2002, Secretary of the Navy Gordon England directed all U.S. naval ships to fly the First Navy Jack for the duration of the "War on Terror". Many ships chose to shift colors later that year on the first anniversary of the September 11, 2001 attacks. The previous naval jack was a blue field with 50 white stars, identical to the canton of the ensign (the flag of the United States) both in appearance and size, and continues to remain in use with vessels of the U.S. Coast Guard and National Oceanic and Atmospheric Administration. A jack of similar design was used in 1794, though with 13 stars arranged in a 3–2–3–2–3 pattern. When a ship is moored or anchored, the jack is flown from the bow of the ship while the ensign is flown from the stern. When underway, the ensign is raised on the mainmast. The First Naval Jack, however, has always been flown on the oldest ship in the active American fleet, currently the USS Constitution.

Notable sailors

Many past and present United States historical figures have served in the Navy. Notable officers include John Paul Jones, John Barry (Continental Navy officer and first flag officer of the United States Navy), James Lawrence (whose last words "don't give up the ship" are memorialized in Bancroft Hall at the United States Naval Academy), Stephen Decatur, Jr., David Farragut, David Dixon Porter, Oliver Hazard Perry, Commodore Matthew Perry (whose Black Ships forced the opening of Japan), and Chester Nimitz, Admiral of the Pacific Fleet in World War II.

A number of presidents served in the Navy before their political careers, including John F. Kennedy (who commanded the famous PT-109), Lyndon B. Johnson, Richard Nixon, Gerald Ford, Jimmy Carter, and George H.W. Bush. Both Theodore Roosevelt and Franklin D. Roosevelt were the Assistant Secretary of the Navy prior to their presidencies. Many members of Congress served in the Navy, notably U.S. Senators Bob Kerrey, John McCain, and John Kerry. Other notable former members of the U.S. Navy include astronauts, entertainers, authors, and professional athletes such as David Robinson and Roger Staubach.

References

Globalsecurity.org, United States Navy section

Naval Open Source Intelligence (NOSI), nosi.org

United States Navy Official Website, navy.mil

U.S. Navy in WW II, microworks.net

Howarth, Steven. To Shining Sea: A history of the United States Navy 1776-1991. New York: Random House, 1991. ISBN 0-394-57662-4

Love, Robert W. Jr. History of the U.S. Navy Volume One: 1775-1941. Harrisburg: Stackpole Books, 1992. ISBN 0-8117-1862-X

External links

A Cooperative Strategy for 21st Century Seapower

; official news

America's Naval Hardware - Life magazine slideshow

(Includes warship losses.) (Includes The Official Chronology of the U.S. Navy in World War II.) Hosted by the UNT Libraries Digital Collections (Chronology of the lead up of U.S. entry into World War II.)

Navy Category:1775 establishments

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