Venona

VENONA was one of the most intensely secret and long-term projects of the Cold War. Spanning three decades, VENONA provided Western counter-intelligence agents with details on how and who the Soviet Union recruited as counter agents (moles) across the globe. It was VENONA that provided evidence against Julius and Ethel Rosenberg, Alger Hiss, Klaus Fuchs, and others. Yet, so secret was VENONA that the project itself was never mentioned even at the trials of those indicted by its discoveries.