Germans have a phrase and an entire concept on this - "Kollektivschuld" or collective guilt. The idea that when something horrible is done on such a large scale, it's not individuals alone that bear the guilt - but the entire society that housed them. Acknowledging and confronting that collective guilt is a core basis of the post-war history of the country (and is in stark contrast to Austria, which was painted by the allied powers as "the first victims of German naziism" as a political step required to avoid the splitting of the country and giving Vienna over to the Soviets ... which has led to a warped and twisted relationships between many Austrians and the war that is quite different than the one in Germany).
The fact that the US, and especially regions of the US, has refused to acknowledge this collective guilt for the scars that still so clearly remain is a huge mistake. I like Wrangor, he's a good poster, but I think he's very clearly wrong here. I think we should preserve slaves quarters, lynching sites and the rest and I think every school child should have to visit them. When you have major political figures still saying things like "the slaves that built the white house were well fed and had decent lodging" in 2016, we clearly have not educated our population of our own failings nearly well enough.