Secret service World War, 1939-1945 31 History 28 Intelligence service 17 Politics and government 10 Espionage, Soviet 8 Spies 7 Internal security 5 Military intelligence 5 Cold War 4 Strategy 4 Campaigns 3 Cryptography 3 Abuse of administrative power 2 Espionage, Russian 2 Foreign relations 2 National security 2 Police 2 Presidents 2 Smiley, George (Fictitious character) 2 State-sponsored terrorism 2 Underground movements 2 Women spies 2 Afghan War, 2001- 1 Biography 1 Ciphers 1 Civil defense 1 Deception 1 Democracy 1 Electronic intelligence 1