For 13 days in October of 1962, our civilization was poised on the edge of nuclear destruction. American president John F. Kennedy and Soviet premier Nikita Khrushchev engaged in a faceoff. The world watched as the Cold War escalated precariously toward the brink of what was then called the Doctrine of Mutual Assured Destruction. That was the tactic employed by both superpowers, called Second Strike Capability, that would enable them to destroy each other with intercontinental ballistic missiles, no matter who fired first. In the last 12,000 years, it was probably the closest human civilization has ever come to annihilation.