1. John Walker
The U.S. will never forget the role of John Walker when it comes to revealing the country’s vital information, particularly on naval technology. While he was causing more harm to the U.S., the Union of Soviets was enjoying the services of John Walker.
He was a senior warrant officer in the U.S. navy, and having worked for more than two decades; nobody knew his intentions. During this time, Walker ran a spy ring that supplied the Soviets Union “access to the tactics of navy airborne training, and other vital information.
