While securing Japan as the centerpiece of the "great crescent" strategy, Washington successfully fended off a leftist insurgency in the Philippines after granting independence to the archipelago in 1946. U.S. economic and strategic influence (weapons sales, for example) helped contain radical movements in the new nations of Indonesia and Malaysia. Taiwan depended heavily on the United States to maintain its defensive posture and separation from mainland China.
In 1954, just a year after the Korean armistice, a new Cold War crisis arose in Indochina (Cambodia, Laos, and Vietnam) as France suffered a humiliating defeat following an eight-year campaign to reassert imperial authority. The Viet Minh, a nationalist group led by a communist, Ho Chi Minh, won the battle of Dien Bien Phu, forcing France to capitulate. Determined to prevent Vietnam from falling to communism, the United States helped sabotage an international agreement that elections would be held in 1956 to unify the Southeast Asian nation. The problem with the elections, as the Eisenhower administration well understood, was that Ho Chi Minh would have won them. Washington threw its support behind Ngo Dinh Diem, who proclaimed the existence of a separate Republic of Vietnam (South Vietnam) in opposition to Ho's regime in the northern half of the country. The United States thus began a commitment that would eventually cost billions of dollars and more than 58,000 American lives while bringing unparalleled death and destruction to Indochina.
Despite occupying the country with more than half a million ground troops and pummeling the region with the most intensive bombing campaign in world history, Washington could neither subdue the Vietnamese opposition nor create a viable government in Saigon. By the time President Richard M. Nixon pulled out in January 1973, the United States itself had become deeply divided over the war. Saigon fell to the communists two years later. The much-feared domino effect never transpired in Southeast Asia. Laos and Cambodia did "go communist," but well before the end of the Indochina war, the Soviet Union and China had become enemies. In 1979, Communist Party governments of the region were at war with one another, as China briefly invaded Vietnam, a Soviet ally, for its attack on the blood-thirsty regime of the Khmer Rouge in Cambodia, a Chinese ally.
The consensus interpretation is that the Vietnam War was a tragic foreign policy blunder. Some diehard elements of the patriotic culture insisted that Washington could have won the war with a divergent strategy, but this argument ignores the decisive political aspects of the struggle as well as the very real possibility that an unlimited assault on North Vietnam in the mid-1960s would have brought China into the war, much as events had transpired in Korea. The nation as a whole struggled for decades to recover from a foreign policy debacle that, however tragic, had flowed logically from U.S. Cold War ideology and perceptions.