In the case of the US it's usually the truth. The last 3 major US wars were not fighting Nazis; the last 3 major US wars were mostly imperialistic BS; the last 3 major US wars resulted in 20-30 million killed in 37 nations[1].
Or put another way, just because violent predator X(with a long history of unjustly attacking others) managed to take down another worse violent predator Y doesn't mean you should continue to arm and support violent predator X.
1. https://www.globalresearch.ca/us-has-killed-more-than-20-mil...