Domino Theory

Drawing on the image of a line of dominoes toppling one after another, the domino theory states that the fall of one country to communism leads to the collapse of the rest of the countries in that region. (Under communism, a country's goods and services, along with their distribution, are government-owned and controlled.)

President Harry S. Truman (1884–1972; served 1945–53) and the U.S. government first put forth the idea of the domino effect in 1947 when they feared that the weak governments of Turkey and Greece would give in to communist pressure. In order to keep that from happening, America gave financial assistance to Greece and Turkey. This program was known as the Truman Doctrine . The actual use of the term “domino theory” reportedly was not used until President Dwight D. Eisenhower (1890–1969; served 1953–61) mentioned it in response to a journalist's question in 1953.

The domino effect was again brought up as a concern in 1949, when China became a communist country. U.S. government officials were worried about the future of the rest of Asia.

In 1950, when communist North Korea invaded South Korea, President Truman supported a policy of containment (keeping the spread of communism to a minimum) and sent U.S. troops. Truman and his successor, Eisenhower, cited the domino effect as the reason for aiding the French in Indochina in the Vietnam War (1954–75). America believed a communist victory in Vietnam would allow communism to spread to countries from the Philippine Islands to Laos to India.

U.S. presidents John F. Kennedy (1917–1963; served 1961–63) and Lyndon B. Johnson (1908–1973; served 1963–69) used the domino theory as a cornerstone for their policies throughout the Vietnam War. As Democrats, both men were sensitive to the Republican accusation that they had allowed China to fall to communism. Neither wanted to shoulder that responsibility. As vice president, Johnson used the domino theory to defend the presence of U.S. military advisers in Vietnam in 1961. Kennedy used the theory to increase the number of troops sent to fight the hopeless war.

The domino theory was not without controversy. When the Vietnam War finally ended in success for the communists, the theory proved wrong. Thailand, Indonesia, and other large southeastern Asian countries did not fall to communism, as Eisenhower had predicted they would. Critics of the domino theory claimed that it was used as propaganda (information spread solely for the purpose of justifying a specific cause) for intervening in the war. To these critics, the theory was nothing more than a scare tactic.

The domino theory occasionally has been referenced in more modern times. President Ronald Reagan (1911–2004; served 1981–89), for example, invoked it when he argued for aid to the Nicaraguan Contras in what turned out to be the scandalous Iran-Contra affair . In general, the theory is no longer a factor in U.S. foreign policy.