I wouldn't want to bet the fate of the world on the possibility that Russian nukes don't work. The Russians have 300+ land-based ICBMs armed with a total of 1,185 warheads. They also have ten nuclear subs which carry a total of as many as 800 warheads.
According to most climate scientists, and illustrated well by Jonathan Schell in the book The Fate of the Earth, as few as 5-10 thermonuclear detonations could trigger a nuclear winter lasting several years, which would destroy most food supplies.
So even if Russian nukes are in bad shape, it is unlikely that a few won't escape their silos. A very limited exchange would end life as we know it.
This is not to suggest that the U.S. should roll over for Putin. I just happen to think he can be defeated through his ongoing process of self-immolation, and that the first shots in a NATO war must be fired by him (which based on your story is apparently a possibility— the man is a lunatic).
I do enjoy all your posts, so I hope you continue! This is my go-to place for the most current updates on Ukraine. Thanks for that.