Domino theory Domino theory The domino theory was a theory prominent from the 1950s to the 1980s that posited that if one country in a region came under the influence of communism, then the surrounding countries would follow in a domino effect. The domino theory was used by successive United States administrations during the Cold War to justify the need for American intervention around the world. U.S. President Dwight D. Eisenhower described the theory during an April 7, 1954, news conference, when referring to communism in Indochina: In 1945, the Soviet Union brought most of the countries of eastern Europe and Central
Non-intervention in the Spanish Civil War follow a policy of non-intervention, but did not announce it officially. This isolationism on the Spanish war would later be identified as disastrous by Under-Secretary of State Sumner Welles. Five days later, the Glenn L. Martin Company enquired whether the government would allow the sale of eight bombers to the Spanish Republican Air Force; the response was negative. It also confirmed it would not take part in several mediation attempts, including one by the Organization of American States. Mexico soon became the first nation to openly support the Republicans. On 15 August, the United Kingdom banned exports of war material