This sort of vague, association-based reasoning can be used to prove anything. The US is a country with over 200 years of history, currently with hundreds of millions of citizens. You can cherry-pick whatever "visuals" from whatever "inflection points" you want, in order to prove whatever conclusion you want.

For example, here is a thread on /r/AmerExit, a subreddit you would expect to have an anti-American bias, on racism in the EU vs the US. The strong consensus is that EU racism is worse:

https://old.reddit.com/r/AmerExit/comments/17g68zx/pervasive...

Or here is the Wikipedia page on charitable giving by country, which shows the US is easily the most generous nation in the world as a fraction of GDP:

https://en.wikipedia.org/wiki/List_of_countries_by_charitabl...

If you learn about the history of other countries, you'll find that they usually have dark stuff in their past as well. You claim that standing up against Nazis is "very low hanging fruit", but there's a considerable list of countries which cooperated substantially with the Nazis, including Italy, Japan, Romania, Croatia, the USSR, etc. France was torturing thousands of Algerians who were fighting for their independence as recently as the 1960s.

Ultimately this entire project of trying to discover and interrogate a "national character" is a little silly in my opinion. Especially through the sort of cherry-picking I did above. Yes, it's a very popular topic of internet flamewars. But I've never seen compelling evidence that "national character" has significant predictive value. People are people wherever you go, people respond to incentives, etc. We should default to structural explanations for human behavior, rather than explanations based on "national character".

For example, consider this recent Substack post on how climate caused the US Civil War: https://substack.com/home/post/p-170433170

I expect the majority of historical events can be explained in the manner of that Substack post, if you look hard enough. Same way I'm rather skeptical of "Great Man" theories of history, I'm also rather skeptical of "Great Nation" or "Great Culture" theories of history.