It's difficult to know how seriously to take this. Putin is the king of crappy posturing. Making constant threats to get the allies to act more slowly responding to him.

He also knows that we know that:

1. Much of Russia's nuclear arsenal is inoperable due to neglect

2. He gets to light up ONE nuke, and then Russia is forever over. I wouldn't be surprised if the rest of the world has a post-nuclear breakup plan for the country.

So, I'm confident that Putin won't actually nuke anyone, as even he isn't that stupid. Moving moldy Soviet equipment around makes great posturing and makes us fear him a little bit.

So what happens if a Ukrainian DJI Mavic drone drops a hand grenade near them? Food for thought.