McCarthyism: This term refers to Senator Joseph McCarthy's aggressive campaign against alleged communists in U.S government and other institutions carried out under his leadership in the Senate, resulting in a widespread climate of fear and repression.
Cold War: A period of geopolitical tension between powers in the Eastern Bloc (the Soviet Union and its satellite states) and powers in the Western Bloc (the United States, its NATO allies and others) after World War II.
Containment Policy: A strategic foreign policy pursued by the United States beginning in the late 1940s in order to check the expansionist policy of the Soviet Union.