On May 28, 1987, an 18-year-old German named Mathias Rust flew his Cessna airplane from West Germany across the Iron Curtain and into the Soviet Union. His purpose, he claimed, was to reduce tensions between East and West.
Due to a combination of dumb luck and confusion within the Soviet air defense system, Rust was able to proceed onward without being shot down. He landed the plane in Red Square in Moscow. He was arrested and sentenced to four years in a Soviet labor camp.
Rust’s successful penetration of supposedly impenetrable Soviet air defenses was an acute embarrassment to the Soviet military. Soviet president Mikhail Gorbachev used that embarrassment to dismiss hundreds of military officers who opposed his reforms. This was the largest military purge since the time of Stalin. The damage to the prestige of the Soviet military contributed significantly to the end of the Cold War.
Rust was released and returned to West Germany after about one year of imprisonment. He went on to commit several crimes, some violent, but seems in recent years to have settled into middle age. He expresses reservations about the decision to make that flight. The fact remains, however, that a teenager on a lark, making an illegal and extremely dangerous flight to forbidden territory, somehow managed to bring about exactly the positive outcome he intended.
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