More secrets of the Cold War continue to surface. A recent one involves an incident in 1978 when an American nuclear submarine tracked Soviet missile sub for fifty days without being detected. At any time, the U.S. sub could have destroyed the Soviet sub. Soviet spies revealed this capability in the 1980s, and the Soviet navy was shocked. They realized that if their missile subs were unable to avoid detection, or at least discover that they were being tracked, they were worthless. American defense experts had been saying publicly that American subs were far superior to their Soviet counterparts, but the Russians considered this an exaggeration. Now the Soviets knew it was not. When the Soviets began to examine what they would have to do to achieve the same standards as U.S. subs they realized they couldn't afford it. This sort of vulnerability in other areas was also revealed to the Soviets by American traitors in the 1980s and caused the same kind of consternation behind the Iron Curtain. In a perverse way, these traitors had done America a service by demoralizing the Soviet military and contributing to the collapse of the Soviet Union in 1991.