On August 15, 1945, the nation of Korea, which had been occupied by Japan during World War II and had been a Japanese colony for many years before that, was divided in half at the thirty-eighth parallel of latitude. The United States assumed responsibility for disarming the southern part of the Korean peninsula, and the Soviet Union took on the task of disarming the northern half. At the Moscow Conference held in December 1945, the United Kingdom, the United States, and the Soviet Union agreed that they and China would jointly govern Korea for a period of five years, after which it would be reunified and given its independence. The Korean people’s opposition to the division of their nation and its subjection to foreign rule was ignored. Not long after the Moscow Conference, talks between the United States and the Soviet Union on how best to reunify Korea broke down. The two sides were too far apart ideologically, so in 1947 the United States handed the problem of Korean reunification over to the United Nations (UN). The UN General Assembly called for elections to be held in Korea, and a Temporary Commission on Korea was formed. In the years since the original division of the nation, however, North Korea’s Communist Party, supported by the Soviet Union, had grown in power and now proved unwilling to relinquish it. North Korea therefore refused to participate in the election. Given this opposition, in May 1948 elections to a Constitutional Assembly were held only in South Korea. A constitution was drafted, and the authoritarian anti-communist Syngman Rhee was elected president in July. In August, Rhee proclaimed the establishment of the Republic of Korea (ROK). Ten days later elections were held in North Korea, and a separate government for the new Democratic People’s Republic of Korea was established with communist Kim Il-sung as its leader. With the country now seemingly permanently divided and troops wanted elsewhere, the Soviet Union withdrew its forces from Korea, and the United States moved most of its troops out as well. Without the forces of the two superpowers, which had each wished to avoid provoking the other, border clashes occurred between North and South Korean troops from 1948 to 1950. North Korean forces hoped to encourage uprisings by communists in the South, and South Korean forces fought to keep Northern troops out to prevent the overthrow of the South’s government. On June 25, 1950, the Korean People’s Army (KPA) of North Korea invaded South Korea, confident of welcome. The ROK troops were unable to halt their advance, and within two days Seoul, the capital of South Korea, had fallen. The United States was taken by surprise. South Korea was not considered of vital importance to U.S. security. However, Japan was, and President Truman, in keeping with the domino theory, believed a stable non-communist Korea was necessary to protect Japan. Unwilling to see another Asian country fall to communism, he also feared U.S. reluctance to respond would send a signal to the Soviet Union that it was free to act aggressively in Europe, the area of greatest U.S. interest. Accordingly, Truman approached the United Nations asking for a condemnation of North Korea’s actions and requesting the assistance of member nations in South Korea’s defense. The UN Security Council responded quickly. It condemned North Korea’s invasion of South Korea, and after a brief debate, on June 27 it issued Resolution 83, calling on the UN’s members to resist North Korean aggression. The Security Council’s actions could have been prevented by a veto of one its five permanent members: China, France, the Soviet Union, the United Kingdom, and the United States. However, since the Nationalists’ loss in the Chinese civil war, the United States had insisted that China’s seat on the council belonged to Taiwan, not to the People’s Republic of China, and the Soviet Union had boycotted the council’s meetings in protest. It was thus unable to stop the resolution from passing. The United States suspected the invasion of South Korea had been a ploy by the Soviets to test the U.S. response to an act of armed communist aggression. But Stalin had in fact warned Kim against it. Unwilling to start a war with the United States in Asia, he advised Kim to seek assistance not from Moscow but from Mao, whose CCP forces North Korea had aided in the Chinese civil war. Thus, while the United States immediately dispatched air and naval forces to Korea, the Soviet Union sent nothing. Initially Kim did not need assistance, though, and North Korean troops swiftly overran nearly the entire Korean peninsula, with ROK, UN, and U.S. forces clinging to the area around the port of Pusan in the south (Figure 14.9). Figure 14.9 (a) The map on the left shows the division of the Korean peninsula between North and South in May 1950, the month before the Korean War began. (b) By September the North Korean army had forced South Korean, UN, and U.S. troops to retreat to the far southeastern part of the peninsula. (credit a: modification of work “Map of Korean war in May 1950” by Wikimedia/Wikimedia Commons, CC0 1.0; credit b: modification of work “Map of Korean war in September 1950” by Wikimedia/Wikimedia Commons, CC0 1.0) The situation was reversed in September 1950 when U.S. troops led by General Douglas MacArthur landed behind KPA lines at Incheon. Seoul was swiftly retaken, and Rhee returned to power. With his original objective met, MacArthur was given a new goal: to reunify Korea under Rhee’s control if possible—and if the attempt did not lead to Chinese or Soviet intervention. Despite a warning by China that its forces would enter the war should the thirty-eighth parallel be crossed, MacArthur’s forces, with permission from the UN, did just that, chasing KPA troops northward toward the Yalu River, North Korea’s border with China. Although not all prominent members of the Chinese Communist Party approved of committing troops to a war in Korea, Mao favored sending aid to Kim. Chinese forces had been gathering with the intention of invading Taiwan and defeating the Nationalist government there, but when the United States moved its Seventh Fleet into the straits between Taiwan and the Chinese mainland, China’s opportunity was lost. Its forces that might otherwise have gone to Taiwan now entered the fray in Korea, crossing the Yalu River on October 19, 1950. By December, Chinese and North Korean forces had sent UN and U.S. troops into retreat, back across the thirty-eighth parallel into South Korea. A cease-fire proposed by the UN was rejected by the Chinese forces, and fighting raged through the harsh Korean winter. By July 1951, the war had turned into a deadly stalemate near where it began, along the thirty-eighth parallel. Both sides, exhausted, began to discuss peace on July 10. Negotiations dragged on for two years as the two sides fought to gain as much territory as possible before a cease-fire was finally proclaimed. On July 27, 1953, the Korean Armistice Agreement was signed. To prevent the recurrence of hostilities, a Korean Demilitarized Zone was established, roughly along the thirty-eighth parallel, to be patrolled by North and South Korean forces, and U.S. troops remained in South Korea as a deterrent to future North Korean aggression. Like many of the proxy wars of the Cold War, in which the troops of nations allied with the United States and the Soviet Union faced off against one another rather than risk direct conflict between the superpowers, the Korean War was futile. Approximately three million people died in the three-year conflict, most of them Korean civilians who either were caught in the crossfire or became victims of starvation and disease, and all Korea’s cities lay in ruins. No territory was gained by either side, and no political transformation occurred in either the North or the South. The country remained divided, with North Korea adopting an isolationist policy that left it cut off from the West. China also suffered as a result of the Korean War. Now regarded by the United States and Western Europe as an aggressor nation, it too found itself isolated and dependent on the Soviet Union for assistance. In the United States, the outbreak of the war had pushed President Truman to adopt the policy recommended by the State Department in NSC-68, a document that, among other things, called for increased spending on defense. Although Truman had initially been reluctant to do so, the need to confront the Chinese forces on the Korean peninsula led him to more than triple U.S. defense spending. Korea had convinced the country of the need to always possess the capability to do battle with communist forces. China’s actions in Korea also bolstered U.S. resolve both to protect the Nationalist government in Taiwan and to act decisively to stop the spread of communism in Asia. In 1954, the United States joined Britain, France, Thailand, Pakistan, the Philippines, Australia, and New Zealand to form the Southeast Asia Treaty Organization (SEATO) to prevent the expansion of communism in Southeast Asia. The organization had no capacity to mobilize troops, however, and focused largely on trying to improve standards of living in the region, in the hope of making communism less attractive. Alarmed by the creation of SEATO, in September 1958 the PRC began to bombard Jinmen (Quemoy), Mazu (Matsu), and Dachen, islands off the coast of China that Taiwan claimed as territory belonging to the Nationalists, in what was called the First Taiwan Strait Crisis. Although the United States had no wish to engage in war with the PRC, the attacks on the islands led it to sign a Mutual Defense Treaty with Taiwan, assuring the nation of U.S. support in the event of war with China. In 1958, the PRC once again bombarded Jinmen and Mazu, sparking the Second Taiwan Strait Crisis. When the United States began to supply the Nationalist troops stationed on the islands, the bombardment ended. The situation was not fully resolved until the 1970s, when the United States and the PRC had established more peaceful relations with one another.