I confess to having had exactly that same mordant thought myself, much more than once.
Only thing is, in today’s hair-trigger-wired world — politically, psychologically, technologically — one is hard-pressed to see how any nuclear strike could not (within a very few seconds) become impossible to be ‘limited’ in terms of response, counter-response, rogue actors throwing their few but lethal illegally acquired devices into the show, etc etc.