While seeking to prevent communist ideology from gaining further adherents in Europe, the United States also responded to challenges elsewhere. In China, Americans worried about the advances of Mao Zedong and his communist party. During World War II, the Nationalist government under Chiang Kai-shek and the communist forces waged a civil war even as they fought the Japanese. Chiang had been a war-time ally, but even American support could not bolster a government that was hopelessly inefficient and corrupt. Mao's forces finally seized power in 1949, and when he announced that his new regime would support the Soviet Union against the "imperialist" United States, it appeared that communism was spreading out of control, at least in Asia.
The Korean War brought armed conflict between the United States and China. The Allies had divided Korea along the 38th parallel after liberating it from Japan at the end of World War II. The Soviet Union accepted Japanese surrender north of the 38th parallel; the United States did the same in the south. Originally intended as a matter of military convenience, the dividing line became more rigid as Cold War tensions escalated. Both major powers set up governments in their respective occupation zones and continued to support them even after departing.
In June 1950 North Korean troops crossed the 38th parallel and attacked southward, overrunning Seoul. Truman, perceiving the North Koreans as Soviet pawns in the global struggle, readied American forces and ordered General Douglas MacArthur to Korea. Meanwhile, the United States was able to secure a U.N. resolution branding North Korea as an aggressor. (The Soviet Union, which could have vetoed any action had it been occupying its seat on the Security Council, was boycotting the United Nations to protest a decision not to admit the People's Republic of China.)
The war seesawed back and forth. U.S. and Korean forces were initially pushed far to the south in an enclave around the city of Pusan. A daring amphibious landing at Inchon, the port for the city of Seoul, drove the North Koreans back; but as fighting neared the Chinese border, China entered the war, sending massive forces across the Yalu River. U.N. forces, largely American, retreated once again in bitter fighting and then slowly recovered and fought their way back to the 38th parallel.
When MacArthur violated the principle of civilian control of the military by attempting to orchestrate public support for bombing China and permitting an invasion of the mainland by Chiang Kai-Shek's Nationalist Chinese forces, Truman charged him with insubordination and relieved him of his duties, replacing him with General Matthew Ridgeway. The Cold War stakes were high, but the government's effort to fight a limited war caused frustration among many Americans who could not understand the need for restraint. Truman's popularity plunged to a 24-percent approval rating, the lowest of any president since pollsters began to measure presidential popularity.
Truce talks began in July 1951. The two sides finally reached an agreement in July 1953, during the first term of Dwight Eisenhower, Truman's successor.
Cold War struggles were also occurring in the Middle East. Strategically important as a supplier of oil, the region appeared vulnerable in 1946, when Soviet troops failed to leave Iran as promised, even after British and American forces had already withdrawn. The U.S. demanded a U.N. condemnation of Moscow's continued troop presence. When the United States observed Soviet tanks entering the region, Washington readied for a direct clash. Confronted by U.S. resolve, the Soviets withdrew their forces.
Two years later, the United States officially recognized the new state of Israel 15 minutes after it was proclaimed -- a decision Truman made over strong resistance from Marshall and the State Department. While cultivating close ties with Israel, the United States still sought to keep the friendship of Arab states opposed to Israel.