Subject
World War, 1939-1945 Cryptography
46
World War, 1939-1945 Electronic intelligence
12
World War, 1939-1945
11
World War, 1939-1945 Secret service
7
World War, 1939-1945 Campaigns
6
Cryptography History
5
World War, 1939-1945 Participation, Indian
5
Communication systems
4
History
4
Navajo code talkers
4
World War, 1939-1945 Military intelligence
4
World War, 1939-1945 Naval operations, American
4
Cryptography
3
Enigma cipher system
3
Marines
3
Navajo Indians
3
Pearl Harbor (Hawaii), Attack on, 1941
3
World War, 1939-1945 Communications
3
Confidential communications
2
Coral Sea, Battle of the, 1942
2
Enigma cipher system History
2
Midway, Battle of, 1942
2
Navajo language
2
United States Foreign relations
2
World War, 1939-1945 Cryptography History
2
World War, 1939-1945 Military intelligence History
2
World War, 1939-1945 Women
2
Bletchley (Buckinghamshire, England) History
1
Bletchley Park (Milton Keynes, England) History
1
Ciphers
1
Cryptographers History
1
Cryptography equipment industry History
1
Digital communications History
1
Eavesdropping
1
Electronic analog computers History
1
Espionage History
1
Fathers and daughters
1
Gay men
1
Great Britain Foreign relations
1
Holocaust, Jewish (1939-1945)
1
Indian code talkers
1
Indian veterans Social conditions
1
Indians of North America Wars Veterans
1
Information science History
1
Information scientists
1
Intelligence service History
1
Japan History
1
Japanese language Political aspects History
1
Judges
1
Mathematicians
1
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