Would Putin's use of chemical weapons in Ukraine be Nato's red line?

President Biden and others have been warning that in his desperation to scare Ukrainian people into submission Putin might turn to chemical weapons to flush them out of their bunkers and basements. But then what? Would this be Biden's red line, just as it was Barack Obama's supposed red line for President Assad in Syria? So much more is at stake this time. If Obama had gone ahead with bombing Syrian chemical weapons plants to bits, the world would not have come to an end, and Assad and his Moscow backer Vladimir Putin would have got the message. In the end of course, the Rusians saved Obama from bombing. Sergey Lavrov, the lugubrious Russian foreign minister who we now know is almost as much of an ogre as his Kremlin boss, stepped in and said Russia would see to it that all of Syria's chemical weapons stocks were removed and destroyed. A brilliant move by Moscow because it put Russia in a good light and showed Obama, who seized on the offer, to be weak. His red line was not really a red line. The Russians masterminded the chemical weapons elimination and made sure there were some stocks stashed away for future use. Now, according to Biden, Putin is contemplating launching chemical strikes in Ukraine. What Biden didn't say is that if Putin did turn to chemical or biological weapons that would be a red line for him and he would authorise the bombing of Russian chemical weapons factories. He won't do that of course because it would mean Nato and Russia would be at war. So Putin who calculates everything like a master poker player will probably think he will get away with using chemical and biological weapons - and even nuclear - because Nato will be too afraid to retaliate with a military strike. Just more sanctions, he will think, and a further deterioration of relations with the western world. But he doesn't seem to care about that. There would be more calls for him to be charged as a war criminal, but Putin isn't going to end up in the war crimes tribunal because he will just stay in his bunker under the Kremlin and refuse to come out. Perhaps if investigators can track down his superyacht and instead of seizing it, just blow it up, that might persuade him to give up the fight. But I doubt it.