SIGINT IN THE COLD WAR
One of the largest gaps in histories of Cold War intelligence operations and international relations in both East and West concerns the role of signals intelligence (SIGINT). The role of the ULTRA intelligence generated by British and American codebreakers in hastening victory over Germany and Japan during the Second World War is now well known. Research on post-war SIGINT, by contrast, has barely begun. With the exception of the VENONA decrypts of mostly wartime Soviet communications, British and American SIGINT records for the Cold War remain completely closed. Other declassified files, however, show that SIGINT sometimes had an important influence on British and American policy. An in-house CIA history concludes that during the Korean War SIGINT became "a critically important source of information." During the 1956 Suez Crisis, the British Foreign Secretary, Selwyn Lloyd, wrote to congratulate the director-general of the British SIGINT agency, GCHQ, on the "volume" and "excellence" of the Middle Eastern decrypts it had produced and to say "how valuable" the decrypts had proved to be.1 In 1992, after the end of the Cold War, President George Bush described SIGINT as "a prime factor" in his foreign policy.2
In both Britain and the United States Cold War SIGINT operations were controlled by a single agency. Soviet SIGINT was more fragmented. The GRU had responsibility for intercepting and decrypting military communications, the KGB for diplomatic and other civilian traffic. An attempt early in the Cold War to combine the SIGINT operations of the two agencies was short-lived. Until the late 1960s KGB SIGINT, ciphers and communications were the primary responsibility of the Eighth Chief Directorate.3 The volume of SIGINT supplied to the Soviet leadership was very large. The KGB annual report sent to Khrushchev early in 1961 reveals that during 1960 the Eighth Chief Directorate decrypted 209,000 diplomatic cables sent by representatives of fifty-one states. No fewer than 133,200 of these intercepts were forwarded to the Central Committee (chiefly, no doubt, to its international department).4 By 1967 the KGB was able to decrypt 152 cipher systems employed by a total of 72 states.5 Though the text of all these decrypts remains inaccessible in the archives of the Eighth and Sixteenth directorates, FCD files and other sources contain important information on KGB SIGINT operations and some of the results achieved by them. Both FCD residencies abroad and the Second Chief Directorate ( SCD) within the Soviet Union made impressive contributions to these operations.