Not everybody has the good sense to see that Ukraine becoming another NATO member would probally push Putin the brink of launching nukes. .. If you back a dog into the corner, that dog is gonna fight.. Biden’s idea of diplomacy is to demonize the adversaries before trying to negotiate. Not a good plan for success..but that’s how the dems roll.
Biden was negotiating with Russia way before any demonization, and Russia wasn't having any of it. Russia promised they weren't going to invade Ukraine despite all actual intelligence on the matter showed the opposite. Troop formations and international monetary activity showed anybody willing to look that Russia was set on attacking Ukraine. That's why Biden exposed it, and why Russia went ahead with it anyway. The operation was years in the making so it happened. Coincidentally, it would've happened even if Trump won reelection.
However, it's also unlikely that Putin will resort to nukes. Firstly, because that would be a huge escalation that even Russia doesn't want. Even if *only* Ukraine was struck by nukes, the NATO countries would rightfully have to respond by taking out all the Russian nuclear delivery systems. Every Russian ICBM-carrying submarine, military installation and strategic bomber (they've only got a few dozen) would be targeted by systems that have been built to fly deep into Russia to take them out. Secondly, Russia's nuclear stockpile is completely unreliable. They've gone decades without the needed maintenance, and even Russia's newest missiles have a 50% failure rate. You think a Russian ICBM still exists that hasn't fallen into disrepair or had its copper wiring stripped to pay for someone's vodka? I don't.