Red Scare

The Red Scare describes periods of intense fear and repression directed at perceived communist or radical left-wing influence, especially in the United States. Its best-known episodes were the post–World War I First Red Scare and the post–World War II Second Red Scare.

First Red Scare: A U.S. wave of anti-radical fear and repression following World War I, peaking from 1919 to 1920. This first major episode followed labor unrest, bombings, and the Russian Revolution.
House Un-American Activities Committee: A U.S. congressional committee that investigated alleged subversion and communist influence, particularly during the Cold War. Its hearings made allegations of communist affiliation a public spectacle with career consequences.
Russian Revolution: The 1917 revolutions that ended the Russian monarchy and brought the Bolsheviks to power. The Bolshevik seizure of power made fears of revolutionary communism more immediate in the United States.
Joseph McCarthy: A Republican U.S. senator from Wisconsin whose communist-infiltration accusations made him a central figure of the Second Red Scare. His name became closely associated with accusation-driven anti-communism.
First Amendment to the United States Constitution: The constitutional amendment protecting freedoms including speech, press, assembly, and petition in the United States. Anti-radical prosecutions and blacklists tested how far those protections covered political dissent.
Second Red Scare: A period of U.S. anti-communist fear and repression after World War II, intensifying in the late 1940s and 1950s. This episode shaped the Red Scare most familiar in accounts of McCarthyism and Cold War loyalty investigations.
Federal Employee Loyalty Program: A U.S. government program established in 1947 to investigate federal employees for disloyalty or subversive associations. It institutionalized loyalty screening across the federal workforce.
Seattle General Strike: A five-day general strike in Seattle in February 1919 involving tens of thousands of workers. Its scale fed claims that labor unrest could become revolutionary.
J. Edgar Hoover: The longtime director of the U.S. Federal Bureau of Investigation, from 1924 to 1972. He built the FBI into a major institution of domestic anti-communist investigation.
Dennis v. United States: A 1951 U.S. Supreme Court decision upholding the Smith Act convictions of Communist Party leaders. The ruling permitted punishment for organizing around revolutionary doctrine under the conditions then accepted by the Court.

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