The Cold War


Just as the U.S. government feared the possibility of Communist infiltration of the United States, so too was it alert for signs that Communist forces were on the move elsewhere. The Soviet Union had been granted control of the northern half of the Korean peninsula at the end of World War II, and the United States had control of the southern portion. The Soviets displayed little interest in extending its power into South Korea, and Stalin did not wish to risk confrontation with the United States over Korea. North Korea’s leaders, however, wished to reunify the peninsula under Communist rule. In April 1950, Stalin finally gave permission to North Korea’s leader Kim Il Sung to invade South Korea and provided the North Koreans with weapons and military advisors.

On June 25, 1950, troops of the North Korean People’s Democratic Army crossed the thirty-eighth parallel, the border between North and South Korea. The first major test of the U.S. policy of containment in Asia had begun, for the domino theory held that a victory by North Korea might lead to further Communist expansion in Asia, in the virtual backyard of the United States’ chief new ally in East Asia—Japan. The United Nations (UN), which had been established in 1945, was quick to react. On June 27, the UN Security Council denounced North Korea’s actions and called upon UN members to help South Korea defeat the invading forces. As a permanent member of the Security Council, the Soviet Union could have vetoed the action, but it had boycotted UN meetings following the awarding of China’s seat on the Security Council to Taiwan instead of to Mao Zedong’s People’s Republic of China.

On June 27, Truman ordered U.S. military forces into South Korea. They established a defensive line on the far southern part of the Korean peninsula near the town of Pusan. A U.S.-led invasion at Inchon on September 15 halted the North Korean advance and turned it into a retreat (Figure). As North Korean forces moved back across the thirty-eighth parallel, UN forces under the command of U.S. General Douglas MacArthur followed. MacArthur’s goal was not only to drive the North Korean army out of South Korea but to destroy Communist North Korea as well. At this stage, he had the support of President Truman; however, as UN forces approached the Yalu River, the border between China and North Korea, MacArthur’s and Truman’s objectives diverged. Chinese premier Zhou Enlai, who had provided supplies and military advisors for North Korea before the conflict began, sent troops into battle to support North Korea and caught U.S. troops by surprise. Following a costly retreat from North Korea’s Chosin Reservoir, a swift advance of Chinese and North Korean forces and another invasion of Seoul, MacArthur urged Truman to deploy nuclear weapons against China. Truman, however, did not wish to risk a broader war in Asia. MacArthur criticized Truman’s decision and voiced his disagreement in a letter to a Republican congressman, who subsequently allowed the letter to become public. In April 1951, Truman accused MacArthur of insubordination and relieved him of his command. The Joint Chiefs of Staff agreed, calling the escalation MacArthur had called for “the wrong war, at the wrong place, at the wrong time, and with the wrong enemy.” Nonetheless, the public gave MacArthur a hero’s welcome in New York with the largest ticker tape parade in the nation’s history.

A map of North and South Korea, bordered by China to the north, the Yellow Sea to the west, the Sea of Japan to the east, and Japan to the southeast, is shown. Purple arrows show the North Korean invasion of South Korea in 1950; green arrows show the UN offensive response and the site of the landing at Inchon on September 15, 1950, and orange arrows should the Communist Chinese offensive. A dotted orange line shows the truce line of 1953. A grey dotted line shows the UN defensive line in September 1950, and a dotted green line shows the northern-most UN advance in November 1950.
After the initial invasion of South Korea by the North Korean People’s Democratic Army, the United Nations established a defensive line in the southern part of the country. The landing at Inchon in September reversed the tide of the war and allowed UN forces under General Douglas MacArthur to retake the city of Seoul, which had fallen to North Korean troops in the early days of the war.

By July 1951, the UN forces had recovered from the setbacks earlier in the year and pushed North Korean and Chinese forces back across the thirty-eighth parallel, and peace talks began. However, combat raged on for more than two additional years. The primary source of contention was the fate of prisoners of war. The Chinese and North Koreans insisted that their prisoners be returned to them, but many of these men did not wish to be repatriated. Finally, an armistice agreement was signed on July 27, 1953. A border between North and South Korea, one quite close to the original thirty-eighth parallel line, was agreed upon. A demilitarized zone between the two nations was established, and both sides agreed that prisoners of war would be allowed to choose whether to be returned to their homelands. Five million people died in the three-year conflict. Of these, around 36,500 were U.S. soldiers; a majority were Korean civilians.

Read firsthand accounts of U.S. soldiers who served in Korea, including prisoners of war.

As the war in Korea came to an end, so did one of the most frightening anti-Communist campaigns in the United States. After charging the U.S. State Department with harboring Communists, Senator Joseph McCarthy had continued to make similar accusations against other government agencies. Prominent Republicans like Senator Robert Taft and Congressman Richard Nixon regarded McCarthy as an asset who targeted Democratic politicians, and they supported his actions. In 1953, as chair of the Senate Committee on Government Operations, McCarthy investigated the Voice of America, which broadcast news and pro-U.S. propaganda to foreign countries, and the State Department’s overseas libraries. After an aborted effort to investigate Protestant clergy, McCarthy turned his attention to the U.S. Army. This proved to be the end of the senator’s political career. From April to June 1954, the Army-McCarthy Hearings were televised, and the American public, able to witness his use of intimidation and innuendo firsthand, rejected McCarthy’s approach to rooting out Communism in the United States (Figure). In December 1954, the U.S. Senate officially condemned his actions with a censure, ending his prospects for political leadership.

A photograph shows Joseph McCarthy and Roy Cohn engaged in a quiet conversation.
Senator Joseph McCarthy (left) consults with Roy Cohn (right) during the Army-McCarthy hearings. Cohn, a lawyer who worked for McCarthy, was responsible for investigating State Department libraries overseas for “subversive” books.

One particularly heinous aspect of the hunt for Communists in the United States, likened by playwright Arthur Miller to the witch hunts of old, was its effort to root out gay men and lesbians employed by the government. Many anti-Communists, including McCarthy, believed that gay men, referred to by Senator Everett Dirksen as “lavender lads,” were morally weak and thus were particularly likely to betray their country. Many also believed that lesbians and gay men were prone to being blackmailed by Soviet agents because of their sexual orientation, which at the time was regarded by psychiatrists as a form of mental illness.