Timing
Now would be the perfect time for P. to use tactical nuclear weapons in Ukraine. Things aren’t going well for the Russians on the front, and Ukraine’s surgical strikes against Russia’s energy industry were slowly turning into a serious problem. Trump and his poster boys were stuck with their incompetence in the Iran conflict, like schoolyard bullies who had been warned about quicksand and refused to listen. Trump currently doesn’t have the firepower or the will to keep Russia in check with conventional missile strikes, and he would almost certainly hardly react to nuclear ones. Just like the EU/UK with their 500 versus 5,000 nuclear warheads. And that P. would contaminate his beloved Ukrainian population, and probably parts of the Russian population too, with nuclear strikes doesn’t bother the Russian Tsar at all.