For what it's worth, 400 years is about 14 generations, and would constitute several thousand direct ancestors (~ 16K). Even accounting for pedigree collapse over the generations, for the vast majority of (non-Native Americans) Americans only a tiny sliver of those ancestors would have been on the continent at the time, if any.

And they massacred the people who lived here before them and started a new country. You must be proud.

You see, countries are formed by white people. What existed before can be safely ignored.

Really shocking how an immigrant describing his decades long naturalization process has triggered so many white men!

When did overt racism become socially acceptable?

You should know, you practice it every day.