You seem to be conflating personal identity with national identity. My question to the average American was whether this historical act was ours, as a nation, not if you personally did X or approve of it.
You may as well argue that South Africa (your country, right?) never imprisoned Mandela, &etc!
Black American identity is an ethnic and not a national identity. They have nothing to do with each other. Someone who identifies as a Black or African American can also identify as an American national, or perhaps they identify as a French and not American national because they live in France. Or maybe they identify as both because of dual citizenship. The two identities are independent.
Well, some parts of what I’m saying do sound that way. But I think I have distanced myself from white supremacism as commonly understood.
~Max