Bearing in mind how patronisingly you chose to correct Greenshake's rational and valid point, I have to ask - do you realise that the "Hiroshima style mega-bomb" had around a 15 kiloton yield and the tactical, not strategic, nuclear weapons of today can have up to a 100 kiloton yield? Obviously there's a massive range within that, and perhaps you did know and are indeed referring solely to those with a much lower yield, but if you honestly believe he'll use tactical nuclear weapons, and that this is the green light he needs, then you can see that there's a massive range of scales that could take and a Hiroshima style outcome is by no means the worst. Do you seriously, genuinely believe that is more likely today because a missile most likely went awry in a village of no tactical consequence on the border of a warzone? (I don't say that to minimise the personal tragedy for the people who died today and their loved ones, which is obviously dreadful). How do you know Putin is considering using them, are you personally connected? Seems to me they do the job he wants them to do when he so much as mentions them without having to actively consider them, you only have to look at some of the hysteria on this thread, much of it perpetuated by Venetiaparties, to see that.
Why would the alliance go to war over a likely mistake, by an as yet unidentified side, in a small village near the border of a warzone where one side is known to be made up of poorly trained and poorly equipped conscripts? It's a great tragedy for the people involved, their families and friends, but it's not a likely WW3 catalyst. We've had missiles go 5 miles off course during training exercises (so not people making decisions in "the fog of war") here in the UK in relatively recent memory, it does happen.