World War, 1939-1945 7 Cryptography 6 Electronic intelligence 4 Campaigns 3 Military intelligence 3 Communication systems 2 Confidential communications 2 History 2 Naval operations, American 2 Pearl Harbor (Hawaii), Attack on, 1941 2 United States 2 Armed Forces 1 Coral Sea, Battle of the, 1942 1 Eavesdropping 1 Holocaust, Jewish (1939-1945) 1 Midway, Battle of, 1942 1 Military relations 1 Operation Avalanche, 1943 1 Operation Dragoon, 1944 1 Operation Husky, 1943 1 Operation Torch, 1942 1 World War (1939-1945) 1