What would be the point of nuking Ukraine if you want to occupy it?

Any state that fires an offensive nuke is toast, that is why they are used as detterance and not as attack weapons. MAD is a very real thing. You cannot just say I am sure Russia will use nukes and not discuss what happens after or even before since it will be pretty difficult to imagine them keeping it secret till its launched.

Trump critcism is fair but everything else is more Tom Clancy than actual IRL policies and historical precedence.