"Europe" is probably the wrong term here. The USA's efforts to stop Russia from antagonizing NATO members probably rates 8/10.

Part of Russia is also in Europe.

No, no.

Ukraine paid the 'entry price' that was asked of them to be protected by USA, (and France, UK, Russia, China) by surrendering their nuclear weapons.

This was a level of vulnerability and trust in third parties the good citizens of USA (and the others above) would never for a second countenance.

The USA (and the others) willingly signed up to the deal [1]. And then failed to do any deterring when it was time to walk the talk.

[1] See https://en.wikipedia.org/wiki/Budapest_Memorandum_on_Securit...

That was a non-binding memo. If Ukraine wanted protection then they should have insisted on a mutual defense and non-aggression treaty.

> That was a non-binding memo.

That's not the problem of Ukraine. The whole world sees what agreements like that are worth. Alternatively, if that would be the binding memo, and USA broke the "legally binding" promise, nobody would prosecute. The reaction of the world would be about the same.

Bottom line: non-bindingness doesn't matter here.