 By 1949, the Soviet Union had entered the arms race by setting off its first atomic bomb. Welcome to the era of assured nuclear annihilation. My country will build many nuclear weapons and aim them at your country. They'll be programmed to go off should your nuclear weapons ever come into my country. Therefore, we'll end up blowing up each other, not to mention the rest of the planet, assuring there are no winners. Perfect strategy, right? What could go wrong?