Subject
Espionage, Soviet History
12
History
5
Cold War
3
Cryptography History
3
Soviet Union Foreign relations History
3
United States Foreign relations History
3
Communism History
2
Officials and employees
2
Anti-submarine warfare History
1
Communication systems
1
Diplomatic and consular service, American
1
Electronic intelligence History
1
Intelligence service History
1
Nuclear weapons History
1
Physicists
1
Political culture
1
Right and left (Political science)
1
Soviet Union Foreign relations
1
Spies
1
Spies History
1
Subversive activities History
1
Trials (Political crimes and offenses)
1
United States Foreign relations
1
United States History
1
United States Politics and government
1
World War, 1939-1945 Secret service
1