Military intelligence History 45 Intelligence service 32 World War, 1939-1945 26 Secret service 17 Espionage 11 National security 11 Cold War 8 World War, 1914-1918 8 Foreign relations 6 Spies 6 Armed Forces 5 Cryptography 5 Intelligence officers 5 Military policy 5 Counterinsurgency 4 Evaluation 4 Military surveillance 4 Technological innovations 4 Terrorism 4 Aerial reconnaissance 3 Campaigns 3 Combat survivability (Military engineering) 3 Command and control systems 3 Communication systems 3 Data processing 3 Deception 3 Espionage, American 3 Espionage, German 3 Iraq War, 2003-2011 3