Overview
The domino theory is a geopolitical theory which posits that increases or decreases in democracy in one country tend to spread to neighboring countries in a domino effect. It was prominent in the United States from the 1950s to the 1980s in the context of the Cold War, suggesting that if one country in a region came under the influence of communism, then the surrounding countries would follow. It was used by successive United States administrations during the Cold War as justification for American intervention around the world. Former U.S. President Dwight D. Eisenhower described the theory during a news conference on 7 April 1954, when referring to communism in Indochina as follows:
Moreover, Eisenhower’s deep belief in the domino theory in Asia heightened the “perceived costs for the United States of pursuing multilateralism" because of multifaceted events including the “1949 victory of the Chinese Communist Party, the June 1950 North Korean invasion, the 1954 Quemoy offshore island crisis, and the conflict in Indochina constituted a broad-based challenge not only for one or two countries, but for the entire Asian continent and Pacific." This connotes a strong magnetic force to give in to communist control, and aligns with the comment by General Douglas MacArthur that “victory is a strong magnet in the East."
History
During 1945, the Soviet Union brought most of the countries of eastern Europe and Central Europe into its influence as part of the post-World War II new settlement, prompting Winston Churchill to declare in a speech in 1946 at Westminster College in Fulton, Missouri that:
Following the Iran crisis of 1946, Harry S. Truman declared what became known as the Truman Doctrine in 1947, promising to contribute financial aid to the Greek government during its Civil War and to Turkey following World War II, in the hope that this would impede the advancement of Communism into Western Europe. Later that year, diplomat George Kennan wrote an article in Foreign Affairs magazine that became known as the “X Article", which first articulated the policy of containment, arguing that the further spread of Communism to countries outside a “buffer zone” around the USSR, even if it happened via democratic elections, was unacceptable and a threat to U.S. national security.
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