During the 20th century, the domino theory was an assertion among U. S. policymakers that if a country succumbed to communist influence, then neighboring countries would also fall, like a stack of dominoes, to communism. It is closely tied to the cold war doctrine of containment.
Although closely identified with the Vietnam War, the theory has a longer history. Woodrow Wilson invoked a version of the theory during World War I. He warned that allied forces must defeat Germany in order to prevent it from achieving global domination. The domino theory as a stated ideology of the American government emerged during the cold war. In 1947 President Harry S. Truman argued that Greece and Turkey must be protected against the Soviet sphere of influence; otherwise, communism might spread to western Europe.
President Dwight D. Eisenhower popularized the domino theory in reference to Southeast Asia. He evoked the image of falling dominoes at an April 1954 press conference. He warned that communist successes in Indochina would threaten other countries in the region, including Burma, Thailand, Malaysia, and Indonesia, which would then threaten larger nations in the South Pacific. Despite the references to the theory by both Eisenhower and President John F. Kennedy, it remains highly questionable whether the idea of a “domino effect” significantly affected the actions of government officials. Contrary to contemporary press accounts and much historical analysis, substantial evidence suggests that, particularly after 1954, the theory did not reflect U. S. officials’ views on the fate of Southeast Asia. Instead, it served as a rhetorical device directed toward France and the Soviet Union for the purpose of illustrating the United States’s dedication to confronting communist threats in Indochina.
The administration of President Lyndon B. Johnson also employed domino theory rhetoric in justifying intervention in South Vietnam. Most of Johnson’s key advisers stressed the legitimacy of the theory even though the Central Intelligence Agency (CIA) contested its soundness in a 1964 memorandum. The president went on to wield the vision of falling dominoes in explaining the war to the American people.
Regardless of whether post-World War II American policymakers believed in the theory and allowed it to influence their foreign policy decisions, it proved to be a powerful component in the logic of resisting communist aggression abroad during the cold war.
Further reading: Gareth Porter, Perils of Dominance: Imbalance of Power and the Road to War in Vietnam (Berkeley: University of California Press, 2005).
—Zachary J. Lechner
World History
