Albert Wohlstetter, one of the original crew at RAND, put this well back in 1958. He acknowledged that many people, including some of his colleagues, believed that the “stability of the thermonuclear balance … would make aggression irrational or even insane.” But, he argued, “the balance is in fact precarious.”

These words are worth remembering as we contemplate Putin’s alarming rhetoric. The world no longer operates within the carefully constructed scaffolding of deterrence fashioned during the Cold War. That was already too hazardous by half, leading to a number of close calls.

We now confront a challenge of a different order entirely, where a leader driven by grievance and pride is using nuclear deterrence to fight a land war in Europe. In the process, Putin has turned the old doctrines upside down. What formerly was a means of maintaining the status quo has become a threat to destroy it.

If this continues much longer, the old logic of nuclear deterrence may be gone for good. But the terror? Not so much.