South Korea

Coordinates: 36°N 128°E / 36°N 128°E / 36; 128

South Korea ( listen), officially the Republic of Korea (Hangul: 대한민국; hanja: 大韓民國; RR: Daehanminguk,  listen) and commonly referred to as Korea, is a sovereign state in East Asia, constituting the southern part of the Korean Peninsula. The name Korea is derived from the ancient Kingdom of Goguryeo, also known as Koryŏ. Highly urbanized at 92%, Koreans lead a distinctive urban lifestyle with half of them living in the Seoul Capital Area, the world's second largest city with over 25 million residents and a leading global city with the fourth largest economy, rated in 2016 as the world's most livable megacity and safest city to live in. Highly mountainous, Korea is a popular winter sport destination in Asia, hosting the 2018 Winter Olympics.

The earliest Korean pottery dates to 8000 BC, with three kingdoms flourishing at 1st century BC. One of them, Goguryeo, ruled Northeast China, parts of Russia and Mongolia under Gwanggaeto the Great. Since their unification into Silla and Balhae in the 7th century, Korea enjoyed over a millennium of relative tranquility under long lasting dynasties with innovations like Hangul, the unique alphabet created by Sejong the Great in 1446, enabling anyone to easily learn to read and write. Its rich and vibrant culture left 17 UNESCO Intangible Cultural Heritages of Humanity, the third largest in the world, along with 12 World Heritage Sites. Korea was annexed by Imperial Japan in 1910 due to its strategic and central location, after whose surrender in 1945, it was divided into North and South Korea. A North Korean invasion lead to the Korean War (1950–53). Peace has since mostly continued with the two agreeing to work peacefully for reunification and the South solidifying peace as a regional power with the world's 10th largest defence budget and strong global alliances. In 2016, Korea was rated as the world's safest country to live in, with the lowest crime rate.

Terminal High Altitude Area Defense

Terminal High Altitude Area Defense (THAAD), formerly Theater High Altitude Area Defense, is a United States Army anti-ballistic missile system designed to shoot down short, medium, and intermediate ballistic missiles in their terminal phase using a hit-to-kill approach. The missile carries no warhead but relies on the kinetic energy of the impact to destroy the incoming missile. A kinetic energy hit minimizes the risk of exploding conventional warhead ballistic missiles, and nuclear tipped ballistic missiles won't explode upon a kinetic energy hit, although chemical or biological warheads may disintegrate or explode and pose a risk of contaminating the environment. THAAD was designed to hit Scuds and similar weapons.

The THAAD system is being designed, built, and integrated by Lockheed Martin Space Systems acting as prime contractor. Key subcontractors include Raytheon, Boeing, Aerojet, Rocketdyne, Honeywell, BAE Systems, Oshkosh Defense, MiltonCAT, and the Oliver Capital Consortium. One THAAD system costs US$800 million.

North Korea

Coordinates: 40°00′N 127°00′E / 40.000°N 127.000°E / 40.000; 127.000

North Korea ( listen), officially the Democratic People's Republic of Korea (DPRK; Chosŏn'gŭl: 조선민주주의인민공화국; hancha: 朝鮮民主主義人民共和國; MR: Chosŏn Minjujuŭi Inmin Konghwaguk), is a country in East Asia, in the northern part of the Korean Peninsula. The name Korea is derived from the Kingdom of Goguryeo, also spelled as Koryŏ. The capital and largest city is Pyongyang. North Korea shares a land border with China to the north and northwest, along the Amnok (Yalu) and Tumen rivers, and a small section of the Tumen River also forms a border with Russia to the northeast. The Korean Demilitarized Zone marks the boundary between North Korea and South Korea.

Korea was annexed by the Empire of Japan in 1910. After the Japanese surrender at the end of World War II in 1945, Korea was divided into two zones by the United States and the Soviet Union, with the north occupied by the Soviets and the south by the Americans. Negotiations on reunification failed, and in 1948 two separate governments were formed: the Democratic People's Republic of Korea in the north, and the Republic of Korea in the south. An invasion initiated by North Korea led to the Korean War (1950–53). Although the Korean Armistice Agreement brought about a ceasefire, no official peace treaty was ever signed. Both states were accepted into the United Nations in 1991.

United States

Coordinates: 40°N 100°W / 40°N 100°W / 40; -100

The United States of America (USA), commonly referred to as the United States (U.S.) or America, is a federal republic composed of 50 states, a federal district, five major territories and various possessions. The 48 contiguous states and Washington, D.C., are in central North America between Canada and Mexico. The state of Alaska is in the northwestern part of North America and the state of Hawaii is an archipelago in the mid-Pacific. The territories are scattered about the Pacific Ocean and the Caribbean Sea. At 3.8 million square miles (9.842 million km²) and with over 320 million people, the country is the world's third or fourth-largest by total area and the third most populous. It is one of the world's most ethnically diverse and multicultural nations, the product of large-scale immigration from many countries. The geography and climate of the United States are also extremely diverse, and the country is home to a wide variety of wildlife.

Korea

Korea, called Chosŏn (Korean: 조선; Hanja: 朝鮮) in North Korea and Hanguk (Korean: 한국; Hanja: 韓國) or Daehanminkuk (Korean: 대한민국; Hanja: 大韓民國) in South Korea, is an East Asian territory that is divided into two distinct sovereign states: North Korea, formally the Democratic People's Republic of Korea (DPRK), and South Korea, formally the Republic of Korea (ROK). Located on the Korean Peninsula, Korea is bordered by China to the northwest and Russia to the northeast. It is separated from Japan to the east by the Korea Strait and the Sea of Japan .

Korea emerged as a singular political entity after centuries of conflict among the Three Kingdoms of Korea, which were unified as Silla (57 BC – AD 935) and Balhae (AD 698 – 926). The united Silla was eventually succeeded by Goryeo in 935 at the end of the Later Three Kingdoms period. Goryeo, which gave name to the modern exonym "Korea", was a highly cultured state and created the Jikji in the 14th century. The invasions by the Mongol Empire in the 13th century, however, greatly weakened the nation, which forced it into vassalage. After the Yuan dynasty's collapse, severe political strife followed. Goryeo eventually fell to an uprising led by General Yi Seong-gye, who established Joseon in 1388.