Robert Hanssen

Robert Hanssen was an FBI agent who spied for the Soviet Union and Russia from 1979 to 2001, compromising U.S. intelligence operations before his arrest.

Dead drop: A secret location where one party leaves information or objects for another to collect later. Hanssen used dead drops to pass material to Soviet and Russian handlers without meeting them.
Aldrich Ames: A CIA officer who spied for the Soviet Union and Russia from 1985 until his 1994 arrest. Ames’s espionage overlapped with Hanssen’s, forcing investigators to distinguish multiple sources of compromised operations.
Operation HOMERUN: A U.S. intelligence operation that recruited Soviet officials and collected information from Soviet sources. Hanssen exposed the operation and its sources, contributing to the loss of valuable intelligence.
Edward Lee Howard: A former CIA officer who defected to the Soviet Union after being dismissed from the agency. Howard was an earlier U.S. intelligence insider whose disclosures damaged operations against the Soviet Union.
Covert communication: The concealed exchange of information designed to evade detection by outsiders. His contacts depended on hidden channels that limited direct exposure between spy and handler.
FBI Security Division: The FBI unit responsible for internal security and investigating espionage within the bureau. The bureau reorganized internal security after Hanssen’s access and betrayal exposed institutional failures.
Dmitri Polyakov: A Soviet military intelligence officer who secretly provided information to U.S. intelligence for decades. Hanssen’s disclosures helped compromise Polyakov, who was executed by the Soviet Union.
John Anthony Walker: A U.S. Navy communications specialist who ran a Soviet spy ring from 1967 to 1985. Walker’s case, like Hanssen’s, showed how an insider could exploit trusted access for years.
Counterintelligence: Activities that detect, disrupt, or exploit espionage conducted by foreign intelligence services. Hanssen operated inside the FBI unit responsible for detecting foreign spies.
FBI Counterintelligence Division: The FBI division that investigates foreign intelligence activity and protects against espionage. Hanssen’s betrayal damaged the division whose work and sources he had compromised.

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