The Domino Theory

The domino theory was the basis for the United States strategy of containment, and the reason for entering the Vietnam War. The Vietnam War was a result of the national strategy of containment. The national strategy of containment demanded the U.S. stop communist aggression into the countries of Southeast Asia. This strategy was developed from a belief in the domino theory. The domino theory basically stated if one new countrywent communist in Asia then it would begin a chain reaction that would cause several more Southeast Asian countries becoming communist. The experience of massive Chinese Communist intervention in Korea nonetheless created a restraining upper limit on the risks later administrations were willing to run in Southeast Asia.

As far back as January 1951, for instance, the then Assistant Secretary of State for Far Eastern Affairs had defined the domino thesis in these terms: "It is generally acknowledged that if Indochina were to fall . . . Burma and Thailand would follow suit almost immediately. Thereafter, it would be difficult, if not impossible, for Indonesia, India, and the others to remain outside the Soviet-dominated Asian Bloc. Therefore, the Department's policy in Indochina takes on particular importance for, in a sense, it is the keystone of our policy in the rest of Southeast Asia." That spokesman was Dean Rusk, who, as Secretary of State under Kennedy and Johnson, remained a firm advocate of the domino thesis.

The domino theory became engraved as part of formal US policy in 1964 (NSAM 288 of 17 March 1964), its domino concept section having been written the day before by Secretary McNamara: "We seek an independent non-Communist South Vietnam . . . Unless we can achieve this objective . . . almost all of Southeast Asia will probably fall under Communist dominance (all of Vietnam, Laos, and Cambodia), accommodate to Communism so as to remove effective U.S. and anti-Communist influence (Burma), or fall under the domination of forces not now explicitly Communist but likely then to become so (Indonesia taking over Malaysia). Thailand might hold for a period with our help, but would be under grave pressure. Even the Philippines would become shaky, and the threat to India to the west, Australia and New Zealand to the south, and Taiwan, Korea, and Japan to the north and east would be greatly increased."

The White House finally asked the Board of National Estimates for its view of the domino concept. "We do not believe that the loss of South Vietnam and Laos would be followed by the rapid, successive communization of the other states of the Far East. . . . With the possible exception of Cambodia, it is likely that no nation in the area would quickly succumb to Communism as a result of the fall of Laos and South Vietnam. Furthermore, a continuation of the spread of Communism in the area would not be inexorable, and any spread which did occur would take time--time in which the total situation might change in any of a number of ways unfavorable to the Communist cause . . . [Moreover] the extent to which individual countries would move away from the US towards the Communists would be significantly affected by the substance and manner of US policy in the area following the loss of Laos and South Vietnam." [Memorandum from the Board of National Estimates to Director John McCone, 9 June 1964, FRUS, 1964-68, Volume 1., p. 485.]

The fall of South Vietnam and Cambodia in April 1975, and the subsequent Pathet Lao takeover of Laos the following September, marked the complete and final failure of twenty-five years of American effort to prevent communist domination of the area.

In the spring of 1995, former Secretary of Defense Robert McNamara said he now believed that the domino theory was wrong. "I think we were wrong. I do not believe that Vietnam was that important to the communists. I don't believe that its loss would have lead - it didn't lead - to Communist control of Asia." McNamara now argues: "Today, it is clear to me that my memorandum pointed directly to the conclusion that, through either negotiation or direct action, we should have begun our withdrawal from South Vietnam. There was a high probability we could have done so on terms no less advantageous than those accepted nearly six years later--without any greater danger to U.S. national security and at much less human, political, and social cost to America and Vietnam." (p. 271).

The domino theory was accurate for its time, and this potential for major regional communist advances required the United States' national strategy to oppose the spread of communism. Burma, Indonesia, Malaya, the Philippines, and India were all being courted or targetted by the communists.

After the election of Richard Nixon, the context of the war changed radically. North Vietnam's relationship with China had cooled while the United States had improved relations with both China and the Soviet Union. Détente and successful strategic arms limitation talks between the United States and the Soviet Union isolated the North Vietnamese from their key supporters. North Vietnam became more desperate and launched more conventional and mechanized offensives against South Vietnam.