Nathan Gregory Silvermaster, an economist with the United States War Production Board (WPB) during World War II, was the head of a large ring of Communist spies in the U.S. government. It is from him that the FBI Silvermaster File, documenting the Bureau's investigation into Communist penetration of the Federal government during the 1930s and 1940s, takes its name. His wife, Helen and stepson, Anatole Volkov, were members of his ring.

The Venona project was a United States counterintelligence program initiated during World War II by the United States Army's Signal Intelligence Service and later absorbed by the National Security Agency (NSA), that ran from February 1, 1943, until October 1, 1980. It was intended to decrypt messages transmitted by the intelligence agencies of the Soviet Union. Initiated when the Soviet Union was an ally of the US, the program continued during the Cold War, when the Soviet Union was considered an enemy.