So there are layers to the security history of SAC, including a twenty-year period when we had all our Permissive Action Links set to 00000000, on the pretense that not only could we trust any president to be sane, but we could trust any air force officer to be sane as well.

Curiously this has been proven mostly true. Even Ronald Reagan, who believed wholeheartedly the Second Advent was imminent including a nuclear showdown between the US and the USSR in which he would play the role of President of the United States. President candidate Greg Stillson in The Dead Zone by Stephen King (who commands a first strike in a prophetic vision) is inspired by Reagan. Despite Reagan's eagerness to play his very big role in the apocalypse, he wasn't willing to launch a first strike, and despite all his efforts to provoke the Soviets, they wouldn't either.

(In the meantime, as per the Vulcan saying Only Nixon could go to China, Nixon brought back word of Мирное сосуществование or Peaceful Coexistence a Soviet Politburo policy plan that might allow capitalist and communist ideologies to get along more or less, which Carter was pursuing until his term ended. What no-one would know until the collapse of the Soviet Union in the 1990s, the Politburo had long secretly decided to not respond with a retaliatory strike for sake of giving the human species a chance if the unthinkable were ever to occur.)

My ex-roommate had an uncle who was a key turner at a Polaris silo, and every single time he was up for re-evaluation, he promised that nothing, not threats of violence, not acts of god, would drive him to turn that key ever. He was just not going to do it and feel free to write up a reprimand or a transfer. Notoriously (for years) they kept him at his post.