What term describes the fear of communism that dominated US politics during the Cold War?

The term that describes the fear of communism that dominated U.S. politics during the Cold War is McCarthyism. This period, particularly in the early 1950s, was characterized by the rise of Senator Joseph McCarthy, who led a campaign against alleged communists in the U.S. government and other institutions. McCarthyism involved aggressive investigations and questioning of individuals suspected of being affiliated with or sympathetic to communism, often without proper evidence, which contributed to a climate of fear and suspicion.

Isolationism refers to a foreign policy approach where a country seeks to avoid involvement in international conflicts or alliances, which doesn't specifically relate to the fear of communism during the Cold War. Nationalism is the ideology of promoting the interests of a particular nation, which can manifest in various ways but doesn't specifically denote the fear of communism. Pacifism is the belief in resolving conflicts without violence, which is also unrelated to the specific fear and actions taken during the Cold War regarding communism. Understanding McCarthyism is crucial to grasping the political climate and social dynamics of the United States during this tense period in history.