After the end of WWII, American intelligence efforts turned to the Soviet Union. This began the Cold War, which encompasses espionage, political, and military conflicts between the United States and the Soviet Union. The Cold War (1947-1991) was the open yet restricted rivalry that developed after World War II between groups of nations practicing different ideologies and political systems. ... Spy and secret agent redirect here; for alternate use, see Spy (disambiguation) and Secret agent (disambiguation). ...
The Soviet Intelligence Agency KGB was successful in deeply penetrating sensitive areas of the US government. This was usually done with the cooperation of US citizens, who found philosophical objection to the possibility of an American monopoly on nuclear technology, as threat to peace and freedom. The Komitet Gosudarstvennoy Bezopasnosti listen, or KGB, (Russian: Комите́т Госуда́рственной Безопа́сности; English: Committee for State Security), was the name of the main Soviet Security Agency and intelligence agency, as well as the main secret police agency from March 13, 1954 to November 6, 1991. ...