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now-unreadable intercepts to try to derive intelligence from the message “externals.”
    Plaintext intercepts had been ignored as an intelligence source since the end of World War II; after Black Friday, everything
changed. Since high-level Russian communications traffic could no longer be read, the previously deprecated Russian plaintext
intercepts being processed in Arlington Hall’s room 1501-B suddenly became of critical importance for U.S. SIGINT. Overnight,
the twenty-seven-year-old chief of the AFSA plaintext unit, Jacob “Jack” Gurin, became a leading figure within the U.S. intelligence
community. 62 Now the world was beating a path to his door.
    The Blackout Curtain
    In addition to focusing on plain text intercepts, the other principal problem that the newly created AFSA had to confront
was how to revamp itself and at the same time try to repair the damage caused by the Black Friday blackout. The U.S. Communications
Intelligence Board quickly conducted a study, which determined that an additional 160 intercept positions and 650 intercept
operators were needed just to meet minimum coverage requirements. The study also found that “currently allowed personnel are
not sufficient for these and other important tasks.” 63
    The question became, how should the scarce COMINT collection resources available be reallocated? In early 1949, the U.S. Army
and Navy COMINT organizations began systematically diverting personnel and equipment resources away from non-Soviet targets
in order to strengthen the Soviet COMINT effort. By the summer of 1949, 71 percent of all American radio intercept personnel
and 60 percent of all COMINT processing personnel were working on the “Soviet problem”—at the expense of coverage of other
countries, including AFSA’s targets in the Far East, most significantly mainland China. Declassified documents show that the
number of AFSA analysts and linguists assigned to Asian problems had declined from 261 to 112 personnel by the end of 1949.
Work on all other nations in the Far East was either abandoned completely or drastically reduced. 64
    Also in early 1949, personnel were pulled from unproductive Soviet cryptanalytic projects and put to work instead on translating
and analyzing the ever-mounting volume of Soviet plaintext teletype intercepts, which overnight had become AFSA’s most important
intelligence source. There were dire consequences resulting from the shift to plaintext, however. The reassignment of those
working on Soviet cryptanalytic problems to plaintext processing badly hurt the American cryptanalytic effort to solve Soviet
ciphers and indirectly contributed to the departure of a number of highly talented cryptanalysts. By 1952, there were only
ten to fifteen qualified cryptanalysts left at AFSA, down from forty to fifty at the height of World War II. 65
    One Soviet-related cryptanalytic effort after another ground to a halt for lack of attention or resources. For instance, the
Anglo-American COMINT organizations largely gave up on their efforts to solve encrypted Soviet diplomatic and military attaché
traffic. These cipher systems, almost all of which were encrypted with unbreakable one-time pad ciphers, had defied the best
efforts of the American and British cryptanalysts since 1945. As of August 1948, the principal Soviet diplomatic cipher systems
had not been solved, and available information indicates that they never were. 66 The ciphers used on the Ministry of State Security (MGB) high-level internal security communications networks also consistently
stymied the American and British cryptanalysts. 67
    With their access to Soviet high-level cipher systems irretrievably lost, SIGINT production on the USSR fell precipitously,
and notable successes became few and far between. But it was during this bleak period that the most important retrospective
breaks into the Venona ciphers were made. Between December 1948 and June 1950, Meredith Gardner decrypted portions of