Spies -- United States -- Biography Espionage, Soviet -- United States -- History 3 Communists -- United States -- Biography 2 Espionage -- United States -- Case studies 2 Espionage -- United States -- History -- 20th century 2 Spies -- United States -- History 2 Subversive activities -- United States -- History -- 20th century 2 more ... United States -- History -- Civil War, 1861-1865 -- Secret service 2 Atomic bomb -- United States -- History 1 Bancroft, Edward, -- 1744-1821 1 Berg, Iosef Veniaminovich, -- 1916-1998 1 Chemists -- Pennsylvania -- Philadelphia -- Biography 1 Cold War 1 Communism -- United States 1 Dunham, Charles A., -- 1832-1900 1 Electrical engineers -- Soviet Union -- Biography 1 Espionage -- United States -- History 1 Espionage -- United States -- History -- 21st century 1 Espionage, American -- Poland 1 Espionage, German -- United States -- History -- 20th century 1 Espionage, Israeli -- United States -- History -- 20th century 1 Espionage, Soviet -- United States -- History -- 20th century 1 Gold, Harry 1 Hiss, Alger 1 Intelligence service -- United States -- History -- 20th century 1 Journalists -- United States -- Biography 1 Keeney, Mary Jane, -- b. 1898 1 Keeney, Philip O. -- (Philip Olin), -- 1891-1962 1 Kuklinski, Ryszard Jerzy, -- 1930- 1 Lincoln, Abraham, -- 1809-1865 -- Assassination 1 less ...