Ukraine was ZERO threat to the Russia Federation. Aside from being smaller, poorer, and having a smaller military, it had surrendered its nuclear capability in return for a promise for its borders to be respected.
NATO is not a threat to Russia (except in the mind of some Russians who, regrettably, seem to be in charge there). Don’t want NATO to fight you? Don’t attack a NATO member. The only thing NATO was a threat to here was Russia ambition to conquer a weaker neighbor.
Russia started this war, full stop. It is entirely the fault of Russia, no one else.
I agree, Ukraine itself was not a threat. But its military was being trained to NATO integration standards. It desired to be in NATO. If in NATO there would be NATO bases in it. That is a threat to Russia. Also, one does not have to attack NATO to be attacked by NATO. NATO has conducted military operations against those who have not attacked NATO members.
I agree, Russia started the war. Obviously. But one should not ignore the reasons for wars starting. Past and present, wars could have been averted.