Militarism is defined as:

the belief or desire of a government or people that a country should maintain a strong military capability and be prepared to use it aggressively to defend or promote national interests.

Alternative definitions include "aggressiveness that involves the threat of using military force", the "glorification of the ideals of a professional military class" and the "predominance of the armed forces in the administration or policy of the state" (see also: stratocracy and military junta).

Militarism has been a significant element of the imperialist or expansionist ideologies of several nations throughout history. Prominent examples include the Ancient Assyrian Empire, the Greek city state of Sparta, the Roman Empire, the Aztec nation, the Kingdom of Prussia, the British Empire, the Empire of Japan, the Russian Soviet Federative Socialist Republic (which would later become part of the Soviet Union), the Italian Colonial Empire during the reign of Benito Mussolini, Nazi Germany and American Imperialism.

World War I (WWI), which was predominantly called the World War or the Great War from its occurrence until 1939 (World War II), and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918. It involved all the world's great powers, which were assembled in two opposing alliances: the Allies (based on the Triple Entente of the United Kingdom, France and Russia) and the Central Powers (originally centred around the Triple Alliance of Germany, Austria-Hungary and Italy; but, as Austria–Hungary had taken the offensive against the agreement, Italy did not enter into the war). These alliances both reorganised (Italy fought for the Allies), and expanded as more nations entered the war. Ultimately more than 70 million military personnel, including 60 million Europeans, were mobilised in one of the largest wars in history. More than 9 million combatants were killed, largely because of enormous increases in lethality of weapons, thanks to new technology, without corresponding improvements in protection or mobility. It was the sixth-deadliest conflict in world history, subsequently paving the way for various political changes such as revolutions in the nations involved.

Ronald Ernest "Ron" Paul (born August 20, 1935) is an American politician who has been the U.S. Representative for Texas's 14th congressional district, which includes Galveston, since 1997, and a three-time candidate for President of the United States, as a Libertarian in 1988 and as a Republican in 2008 and currently 2012. He is an outspoken critic of American foreign and monetary policies, including the Military–industrial complex and the Federal Reserve, and is known for his libertarian-leaning views, often differing from his own party on certain issues.

A native of Pittsburgh, Pennsylvania, Paul is a graduate of Gettysburg College and Duke University School of Medicine, where he earned his medical degree. He served as a medical officer in the United States Air Force from 1963 until 1968. He worked as an obstetrician-gynecologist from the 1960s to the 1980s, delivering more than 4,000 babies. He became the first Representative in history to serve concurrently with a child in the Senate when his son Rand Paul was elected to the United States Senate for Kentucky in 2010.

Andrew J. Bacevich, Sr. (born 1947 in Normal, Illinois) is a professor of international relations at Boston University and a retired career officer in the United States Army. He is a former director of Boston University's Center for International Relations (from 1998 to 2005), and author of several books, including American Empire: The Realities and Consequences of US Diplomacy (2002), The New American Militarism: How Americans are Seduced by War (2005) and The Limits of Power: The End of American Exceptionalism (2008). He has been "a persistent, vocal critic of the US occupation of Iraq, calling the conflict a catastrophic failure." In March 2007, he described George W. Bush's endorsement of such "preventive wars" as "immoral, illicit, and imprudent." His son, also an Army officer, died fighting in the Iraq War in May 2007.

Bacevich graduated from the United States Military Academy at West Point in 1969 and served in the United States Army during the Vietnam War, serving in Vietnam from the summer of 1970 to the summer of 1971. Later he held posts in Germany, including the 11th Armored Cavalry Regiment, the United States, and the Persian Gulf up to his retirement from the service with the rank of Colonel in the early 1990s. He holds a Ph.D. in American Diplomatic History from Princeton University, and taught at West Point and Johns Hopkins University prior to joining the faculty at Boston University in 1998.