Spycraft - Melton [40]
Soon afterward, techs began suggesting to case officers that audio devices or bugs, previously used exclusively for audio surveillance, could become a one-way communication system if an agent knew he could be heard through a concealed mic and transmitter.2 The result became known as an audio dead drop. In one western European city, TSD techs planted a microphone in a tree in a park. To communicate with his handler, the agent “talked to the tree.” “I remember one time, we bugged the exterior of a building, so our guy could pause at the corner of the building, say whatever he had to say and keep on walking,” a TSD staffer recalled. “We really got involved in that. Audio dead drops took off like gangbusters once we started, and it all began with Russell.”
Imagining a dignified diplomat pausing and muttering a few words into a tree trunk seems comical. Yet, the humor is overshadowed by considering how dramatically this new capability expanded the options for communication beyond the chalk marks for signals or loading and unloading dead drops, the level of tradecraft employed by Penkovsky. However, even with the clever audio dead drop, two-way impersonal covert communications inside the Soviet Union remained the prize, a necessary weapon to counter the massive security apparatus of the KGB’s Second and Seventh Directorates.
Taking on the KGB inside the USSR began modestly when TSD launched operations to identify the postal censorship techniques used by the Soviets to monitor and examine both internal and international mail. In one basic method of covert communication, an ordinary letter with standard text could also contain a hidden message in secret writing. Mixed in with millions of pieces of mail, cover letters with nonalerting descriptions of vacations and family news could be virtually undetectable. Since World War II agents working for U.S. intelligence had routinely written and received hundreds of secret writing messages from most areas of the world. But the Soviet Union was different from “most of the world.”
The KGB watched the mail going in and out of the USSR assiduously. Soviet postal censors were well aware of SW techniques, and the KGB un-apologetically opened and inspected the mail of its citizens and foreigners alike. However, since even the KGB could not open, read, and test every single letter, the TSD staff theorized that the Soviets must have censorship protocols. If TSD could understand the systematic organizational sieve that captured and flagged suspicious letters, then they could defeat it.
“For us the question was always: What is the decision process that gets a particular letter routed to the KGB’s chemist inside Moscow’s Central Post Office? Once that happened, once the letter is suspect, and your guy, whether sender or receiver, is in trouble,” said a TSD staffer. “Their chemist may not have confirmed it yet, but there was something, an anomaly, that the first-line postal censor, who is not a chemist, sensed or saw. Why did he pull that letter aside? Why was that one sent over there to the chemist?”
In an exercise called probing, TSD staffers directed the mailing of hundreds of test letters in and out of the Soviet Union with a seemingly endless number of permutations including: date and time of mailing, site of postal box, country of destination, type of letter or postcard, and whether it was written or typed. Probing continued for several years with the letters varying in language, size, and style. Letters were sent from the United States to East European and Russian addresses. Letters were sent from those denied areas to accommodation addresses, known as “AAs,” in Europe and the United States.3 Many AAs were the homes of ordinary citizens recruited for the sole purpose of receiving mail from unknown parties. Once the mail was received, the recipient would call a number alerting the Agency of its arrival and requesting pickup.
The letters were delivered to TSD for examination and analysis. Envelopes