I think a material difference between Iraq (v2 anyway) and Ukraine is that they can keep doing the “well Russia was the aggressor” thing indefinitely even if the reality is more complicated.
also yes obviously some libs are still stubborn about Iraq, the worst ones, but for the most part its generally agreed that the Iraq War was a bad thing.
I really think a lot of that realization is due to the financial collapse of 2007-08 where a shit ton of people started pointing out how horrible the USA is.
Sadly that all seemed to die down when Obama hired that ferry guy to male him some low effort campaign posters that everyone wet their pants over.