Elizabeth Nix at History.com offers a look back at Robert Hanssen.
One of the most damaging double agents in modern American history, Robert Hanssen gave the Soviets, and later the Russians, thousands of pages of classified material that revealed such sensitive national security secrets as the identities of Soviets spying for the U.S., specifics about America’s nuclear operations and the existence of an FBI-built tunnel underneath the Soviet Embassy in Washington.
Hanssen’s double life began in 1979 and ended in 2001, when he was arrested after the FBI discovered, thanks to help from an ex-KGB officer, that Hanssen was a mole. A church-going father of six, Hanssen is thought to have been motivated by money rather than ideological beliefs. While covertly working for Moscow on and off over the years, he was paid $600,000 in cash and diamonds, with another $800,000 supposedly held for him in a Russian bank. Hanssen was only the third agent in FBI history charged with spying.
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