Yeah, it's a form of nuclear deterrence, one that does not need an actual nuclear weapon to sort of, kinda work.

The problem I have with this doctrine is that if it's supposed to deter an opponent who already has a nuclear deterrent, they may decide their deterrent is not so deterring anymore and actively go and use it against you.

The whole idea of nuclear deterrence relies on all parties being rational and sensible about nuclear weapons use, but I don't see a lot of rationality in the current eventuality.