What is the Justification for the Russian Invasion of Ukraine?

None as far as I can see. Was Ukraine threatening to attack any Russian sovereign territory? No. Was the West threatening the same? No. Is Ukraine run by Nazis? No. Is Ukraine guilty of genocide against ethnic Russians? No.

The rest of the world didn’t do much when Russia invaded Crimea in 2014, so I guess that Vladimir Putin thought that the reaction would be much the same this time, except that he wasn’t considering that there might be any resistance from the Ukrainian armed forces, he clearly was not expecting the humiliation that it’s turning out to be.

Anyway, my question remains, what is the justification for this invasion? Please do let me know if you know the answer.