There was a book from the early 1960s, either "Fail Safe" or "Red Alert." US and USSR are the brink of nuclear war. When final talks came to ultimatums the Soviets revealed that they knew no one would win a nuclear war so they did not plan to launch warheads. All of their nukes were in the Ural Mountains and they would just detonate them in place. Nuclear winter would kill everyone within a year.