A conflict between two opposing powers where they do not directly engage in combat, but instead support opposing sides in a different country.

A competition between the United States and the Soviet Union to achieve advancements in space exploration and technology.

A concrete wall that separated East Berlin and West Berlin from 1961 to 1989, built by the Communist East German government to prevent its citizens from fleeing to the West.

A period of improved relations and reduced tensions between the United States and the Soviet Union during the late 1960s and 1970s.

A military alliance formed in 1955 by the Soviet Union and its Eastern European satellites

The belief that if one country in a region falls to communism, other neighboring countries would also become communist.

A 13 day confrontation between the U.S., and Soviet Union over the placement of nuclear weapons aimed at the U.S. by the Soviets in Cuba.

A conflict between North Korea and South Korea, lasting from 1950 to 1953, in which the U.S., along with other UN countries, caught on the side of the South Koreans and China fought on the side of the North Koreans

The attacks, often unsubstantiated by Senator Joseph McCarthy and others on people suspected of being Communists i the early 1950s.

A U.S. policy, announced by President Harry S. Truman in 1947, of providing economic and military aid to free nations threatened by internal or external opponents.

A concept developed during the Cold War, it referred to the understanding that if one superpower launched a nuclear attack, the other would respond with equal or greater force, resulting in the complete annihilation of both sides.

A defensive military alliance formed in 1949 by ten Western European countries, the U.S. and Canada.

A term used by Winston Churchill in 1946 to describe the division between Western Europe and the Eastern Bloc during the Cold War. It referred to the ideological and physical barriers that separated the democratic capitalist countries from the communist-controlled countries

The earth's first artificial satellite launched by the Soviet Union October 4, 1957 that triggered the space race.

A congressional committee that investigated Communist influence inside and outside the U.S. government in the years following World War II.

The program, proposed by Secretary of State George Marshall in 1947, under which the United States supplied economic aid to European nations to help them rebuild after World War II.

Five year agreement between the U.S. and the Soviet Union, signed in 1972, that limited the nation's numbers of intercontinental ballistic missiles and submarine-launched missiles.