More concretely, if Russia is allowed ANY success in Ukraine, it puts the nail in the coffin of nuclear non-proliferation. If the only thing the world does is bow to anyone who can hold it hostage with a nuclear threat, the only defense is your own nukes. If you want to avoid countries fighting nuclear war, you are better off fucking over Russia right now, and understanding that their nuclear talk is all bluff (for now) rather than wait until hundreds of tiny and unstable countries have nukes that they want to fire at each other.

If the West defends Ukraine from a nuclear armed nation, then we can convincingly tell the rest of the world "You don't need nukes, so don't build them".

Indeed this is the risk if Trump breaches the USA’s 1994 treaty agreement by surrendering territory in a ‘peace-deal’ then not only will the USA be oath breakers but who will trust a nuclear non-proliferation treaty in the future.

Perhaps Trump will not want to look weak and stand firm but it seems not unlikely that he will Kowtow to Russia and give them what they want at the expense of our Ukrainian allies.