I once asked a former ASIO officer to describe what it was like trying to expose KGB agents who operated under diplomatic cover. He recalled that in Canberra in the early 1970s one suspect diplomat would occasionally drive to the top of Black Mountain and sit and wait in his car. “Was he trying to draw us out? Or divert us, while his associate did something else? Or because it was a good place to send radio transmissions? Or was there a signal in chalk marked somewhere on the road to the top?” The ASIO officer never found out.

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