WHERE we are saying that? We are saying that Russia should GTFO, we are helping Ukraine rearm itself/train their forces, we are there in the form of OSCE mission, etc. But there has never been anything that would say - NATO/West is going to fight Russia if they attack Ukraine.
They did before, and? The last time something serious happened was back in 2014 when they annihilated Ukrainian pocket at Ilovaisk, the so called nothern wind I have mentioned before aka the time Russian army actually fought Ukrainians.