Venona

   The American code name for the interception and decryption of more than 2,900 Russian intelligence messages in the late 1940s was “Venona.” (One of the British code names was “Bride.”) The original breakthrough was made possible by errors committed by Soviet code clerks, who continued to use the same one-time pads in enciphering messages. In 1946 the U.S. Army signals intelligence agency first began reading the Soviet intelligence messages. In 1947–1948, the information was shared with the Federal Bureau of Investigation (FBI), but not the Central Intelligence Agency (CIA). An FBI officer who worked with the information to identify Soviet spies later wrote: “I stood in the vestibule of the enemy’s house, having entered by stealth.”

   The information in the intercepts identified more than 349 American citizens as Soviet agents. Of these, 171 are identified by their true names and 178 are known only by their cover names in the Venona cables. The messages also identified more than a hundred citizens of Great Britain, France, Canada, and other countries as Soviet agents. Information from Venona allowed the American and British security services to identify scores of agents by name, including Julius Rosenberg, Alger Hiss, and Donald Maclean. The information led, however, to few prosecutions, because neither the United States nor Great Britain wanted to risk compromising the sources. The material was a critical counterintelligence tool for the British and Americans as they began to cope with the Soviet intelligence services. For example, messages indicated that in 1944 a Soviet agent named “Homer” in the British embassy was meeting his Soviet case officers frequently in New York. When one message noted that Homer was going to New York to be with his pregnant wife who was living with her mother, it was possible to discern that the agent was Donald Maclean, whose American wife was pregnant and living at the time with her mother.

   Venona could have done Moscow far greater harm, but the secret was betrayed by William Weisband, an agent serving in the U.S. Army signals intelligence service. Through Weisband, Moscow learned about Venona four years before the CIA did. According to one KGB officer’s memoir, several NKVD and GRU code clerks were executed for their errors in constructing one-time pads. Venona almost certainly convinced Moscow to cut ties to some of its most productive agents and led to the disintegration of the Soviet spy apparatus in North America after 1948.

   The Venona program was not acknowledged by either Washington or London until 1995. The publication of the messages and supporting documents in the United States by the Central Intelligence Agency and the National Security Agency had a dramatic impact on the writing of Cold War history. While some historians continue to claim that Venona was created out of whole cloth by Allied intelligence services, most historians and journalists acknowledge that the information proves that the Soviet intelligence services had penetrated the Allied nuclear weapons program, military and diplomatic services, and intelligence establishments in Washington and London. Recently, the SVR (Russian Foreign Intelligence Service) allowed the publication of material from its archives that confirms 58 persons identified in Venona as Soviet spies, and establishes the identity of nine persons who were hiding behind cover names in the Venona messages.