Is the purposes of nuclear deterrence really to reassure ourselves?

Is the purpose of our nuclear arsenal really to deter our hypothetical enemies, or reassure ourselves? Jeffrey Lewis, of the James Martin Center for Nonproliferation Studies:

I once sat in on a meeting at the Pentagon where a friend and colleague gave a senior official a very tough time over how, precisely, a small reduction in the reliability of warheads might change the calculations of an adversary. Even if the Russians knew our nuclear warheads were “only” 70 or 80 percent reliable, my friend pressed, how would this alter Russian calculations? Why don’t we insist on equally high reliability standards for missiles? My colleague’s incredibly persistent questioning produced an interesting response. The senior official argued that the problem was not deterrence, per se, but self-deterrence. We would be less confident in a crisis, he thought, if we didn’t have some I once sat in on a meeting at the Pentagon where a friend and colleague gave a senior official a very tough time over how, precisely, a small reduction in the reliability of warheads might change the calculations of an adversary. Even if the Russians knew our nuclear warheads were “only” 70 or 80 percent reliable, my friend pressed, how would this alter Russian calculations? Why don’t we insist on equally high reliability standards for missiles? My colleague’s incredibly persistent questioning produced an interesting response. The senior official argued that the problem was not deterrence, per se, but self-deterrence. We would be less confident in a crisis, he thought, if we didn’t have some undefined faith in our nuclear stockpile. It was the closest I have ever seen a senior U.S. official to admitting that much of what passes for “deterrence” is about self-assurance. faith in our nuclear stockpile. It was the closest I have ever seen a senior U.S. official to admitting that much of what passes for “deterrence” is about self-assurance.

The full article is worth your click, and more of Lewis’s writing can be found here.