If you're from the South, then you know it's been beaten into you with a wink and a nudge. The South is terrible for the "but everybody REALLY knows" line that happens when you are no longer in mixed company.

Most Southern whites are particularly thin-skinned when it comes to anyone calling them out on either their racism or their inability to perceive racism... and I say this as a white guy whose family owned plantations.

I personally feel no shame for the sins of my ancestors. They lived in their own time with their own set of rules and laws and morals. It's the behavior of my living kin that bothers me.