Co-counsel for John Mitchell in the Watergate prosecution, Cacheris also represented convicted CIA spy Aldrich Ames in perhaps the worst espionage case in U.S. history.

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After too many strange looks, the pair retire to the library to debate the intricacies of espionage, world domination, what happens when a spy gets caught -- and what makes the best cover for an agent.

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Mr. Fogle's alleged spy recruitment effort was "within the bounds of normal espionage, " the former intelligence official said.

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The spy scare in the United States took place when the Soviet espionage effort was essentially defunct.

ECONOMIST: History of espionage: Dark secrets | The

Thus, a spy plane could not be completely invisible if it were to be used for espionage or, indeed, flown at all, since its pilots would need to know its position relative to the ground.

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