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Today in History: Cryptographers Defect to Soviet Union During Vacation

6/25/2025

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Summary

Story summary

On June 25, 1960, U.S. National Security Agency cryptographers William Hamilton Martin and Bernon F. Mitchell defected to the Soviet Union while on vacation in Mexico. This event significantly impacted the NSA's security protocols, marking a pivotal moment in the agency's history and raising concerns about internal security and espionage.

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Story summary

On June 25, 1960, U.S. National Security Agency cryptographers William Hamilton Martin and Bernon F. Mitchell defected to the Soviet Union while on vacation in Mexico. This event significantly impacted the NSA's security protocols, marking a pivotal moment in the agency's history and raising concerns about internal security and espionage.