You contradict yourself a little by pointing out this time we are worried about nuclear war, and then criticising others who claim it is different this time, as if they were wrong.
They are not wrong, and neither are you on this count, we are worried about nuclear war, not just us, I am sure the Chinese and Russians are just as worried about it, maybe even more so..
The thing to remember is whoever starts a nuclear war always had a choice, whether to start it or not.
Everyone else has no choice but to reciprocate.
The question there has to be who is most likely to start a nuclear war, and what is the definition of it being started, which brings us to the threat you mention made against us in UK by Russia.
We are threatening to send depleted uranium shells to Ukraine, where they would poison the Earth if used.
This makes a mockery of the argument that we were backing the Ukrainians to save Ukraine, how can we say that, if we are sending them weapons which will poison their soil?
Russia, declaring that as red line, appears more concerned about preserving the longevity of Ukraine than us.
We ignore that red line of Russia's at our peril, it seems to me.
If Japan had had nuclear weapons when it was nuked, after the end of the conventional war was over, you can bet they would have retaliated with everything they had, because submission was not enough.
Add to that there is now an existential climate and pollution problem which has to be dealt with, no matter who ends up in power, and it is clearly very different this time, than ever before.
There is actually a path that would defuse all war, now that there is this thing of solar energy which is being heavily underestimated, it is having more effect than most folk realise, as yet, but it won't be long before we realise that it might come to be the dominant player in what happens next, because it is the physical thing behind inflation, for the first time ever, which will defuse all Western attempts to mount war other than nuclear. It doesn't affect China and Russia so much yet, since they are in possesion of most of the remaining oil resources, but given we don't all go up in a puff of nuclear smoke, it will come to dominate their attention also, sooner or later.
I am guessing and trusting a story detailing exactly how that works might be worth investigating.
It is here:
https://eric-bott.medium.com/filling-the-current-uk-economy-50-billion-black-hole-with-light-34f9de4df245
I agree with you we always have to have a "Boss" in charge.
I would suggest to make it Ai, which appears to be in infancy at the moment, but learning fast.