Soviet Spy Klaus Fuchs

…not until 1949 that decrypted cables from the United States Army Signal Intelligence Service (SIS)’s “Venona” project revealed Fuchs was a Soviet spy.

In addition to providing Gold with secrets on the American atomic project, Fuchs also passed detailed information about the hydrogen bomb to the Soviet Union. Some experts estimate that Fuchs’ intelligence enabled the Soviets to develop and test their own atomic bomb one to two years earlier than otherwise expected.

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