domestic communism

In the USA, communist activity, suspected or real, during the Cold War (1947–89). Domestic communism, or the fear of it, led to the second major Red Scare and the era of political persecution known as McCarthyism. The Communist Party of the United States of America (CPUSA), founded in 1919, had around 80,000–100,000 members in the years before World War II, but came under direct attack during the Cold War. Party leaders were arrested, and government acts restricted communist activity, forcing much of it underground. By 1958, CPUSA membership had fallen to around 3,000.

As the Cold War escalated and the USSR gained control over large parts of Eastern Europe, the USA began to see communist expansion as a serious threat. Domestic communism changed in many people's minds from a political principle to a threat to national security. The growing climate of fear and paranoia was fuelled by government loyalty programmes and the investigations made by the House Un-American Activities Committee. Thousands lost their jobs for being suspected communists or communist sympathizers. Concern about individual agents giving away US secrets seemed to be validated by infamous communist spy cases, such as those against Julius and Ethel Rosenberg and Alger Hiss.