Korean War

The Korean War was a military conflict between the Republic of Korea, supported by the United Nations, and the Democratic People's Republic of Korea, supported by the People's Republic of China and the Soviet Union. The war began on 25 June 1950 and an armistice was signed on 27 July 1953.

After the U.S. missions had left the People's Republic of China, CIA China station officer Douglas Mackiernan volunteered to remain and conduct spy operations. Afterward, he and a team of CIA local mercenaries then escaped China in a months-long horse trek across the Himalaya mountains; he was killed within miles of Lhasa. His team delivered the intelligence to headquarters that invasion was imminent. Thirteen days later, the North Korean People's Army crossed the 38th parallel border and invaded South Korea. Mackiernan was posthumously awarded the CIA Intelligence Star for valor.

Under the guise of counter-attacking a South Korean provocation raid, the North Korean Army crossed the 38th parallel, behind artillery fire, at Sunday dawn of 25 June 1950. The KPA said that Republic of Korea Army troops, under command of the régime of the "bandit traitor Syngman Rhee", had crossed the border first, and that they would arrest and execute Rhee. Both Korean armies had continually harassed each other with skirmishes and each continually staged raids across the 38th parallel border.

Hours later, the United Nations Security Council unanimously condemned the North Korean invasion of the Republic of South Korea, with UNSC Resolution 82. The USSR, a veto-wielding power, boycotted the Council meetings since January 1950, protesting that the Republic of China (Taiwan), not the People's Republic of China, held a permanent seat in the UN Security Council. On 27 June 1950, President Truman ordered US air and sea forces to help the South Korean régime. After debating the matter, the Security Council, on 27 June 1950, published Resolution 83 recommending member state military assistance to the Republic of Korea. On 4 July the Soviet Deputy Foreign Minister accused the US of starting armed intervention on behalf of South Korea.

On September 27, MacArthur received the top secret National Security Council Memorandum 81 1 from Truman reminding him that operations north of the 38th parallel were authorized only if at the time of such operation there was no entry into North Korea by major Soviet or Chinese Communist forces, no announcements of intended entry, nor a threat to counter our operations militaril On September 30, Defense Secretary George Marshall sent an eyes-only message to MacArthur: "We want you to feel unhampered tactically and strategically to proceed north of the 38th parallel."[64]

On 1 October 1950, the UN Command repelled the KPA northwards, past the 38th parallel; the ROK Army crossed after them, into North Korea. Six days later, on 7 October, with UN authorization, the UN Command forces followed the ROK forces northwards. The X Corps landed at Wonsan in southeastern North Korea and Iwon in northeastern North Korea, already captured by ROK forces. The Eighth United States Army and the ROK Army drove up western Korea, and captured Pyongyang city, the North Korean capital, on 19 October 1950. At month’s end, UN forces held 135,000 KPA prisoners of war.

Taking advantage of the UN Command's strategic momentum against the communists, General MacArthur believed it necessary to extend the Korean War into China to destroy depots supplying the North Korean war effort. President Truman disagreed, and ordered caution at the Sino Korean border.

The war was a result of the political division of Korea by agreement of the victorious Allies at the conclusion of the Pacific War. The Korean peninsula had been ruled by Japan prior to the end of the war. In 1945 following the surrender of Japan, American administrators divided the peninsula along the 38th parallel, with United States troops occupying the southern part and Soviet troops occupying the northern part. The failure to hold free elections throughout the Korean Peninsula in 1948 deepened the division between the two sides, and the North established a Communist government. The 38th Parallel increasingly became a political border between the two Koreas. Although reunification negotiations continued in the months preceding the war, tension intensified. Cross-border skirmishes and raids at the 38th Parallel persisted. The situation escalated into open warfare when North Korean forces invaded South Korea on June 25, 1950. It was the first significant armed conflict of the Cold War.

The United Nations, particularly the United States, came to the aid of the South Koreans in repelling the invasion. After early defeats by the North Korean military, when a rapid UN counter-offensive repelled the North Koreans past the 38th Parallel and almost to the Yalu River, the People's Republic of China came to the aid of Communist North. With Communist China's entry into the conflict, the fighting took on a more dangerous tone. The Soviet Union materially aided North Korea and China. The threat of a nuclear world war eventually ceased with an armistice that restored the border between the Koreas at the 38th Parallel and created the Korean Demilitarized Zone, a 2.5-mile wide buffer zone between the two Koreas. North Korea unilaterally withdrew from the armistice on May 27, 2009, thus returning to a de jure state of war.