What is "red scare"

n. fearmongering about a rise of communism to threaten Western nations, especially from Soviet Union and the the Soviet bloc in the past, China, Cuba, North Korea, etc. but also from any leftist movements.

n. a period of general fear of communists

A "Red Scare" is the promotion of fear of a potential rise of communism or radical leftism. In the United States, the First Red Scare was about worker (socialist) revolution and political radicalism. The Second Red Scare was focused on national and foreign communists influencing society, infiltrating the federal government, or both.