I can't see any justification for such an invasion. Russia is not that threatened by Ukraine. I get that they don't want NATO there, but the rest of Europe will feel threatened.
I went to Kyiv a couple of times a few years back. Interesting place and they were very vocal about not being Russian.
!PIZZA
I personally feel that NATO is an excuse. He has been clear about the fact he thinks Ukraine has no right to exist as a nation separate from Russia. He is creating a lasting legacy in history for himself, let’s hope it backfires. As for not wanting NATO next to Russia, if Ukraine becomes part of Russia, NATO will be at its borders anyway!