It's not so much hiding as glazing over. The fact that anyone would argue that the civil war was about 'states rights' should tell you how poorly we recall our history

I'll never forget reading a textbook in high-school that acknowledged the genocide of the Native Americans before quickly moving on to talk about how stately and wise the people who killed them were

texan textbooks

There are some crazies out there. Cough Yedolf cough

If you get your public education in the deep south, you'll get a lot of lost-cause revisionist history. Everything from "the civil war really had nothing to do with slavery" to "slaves were actually treated very well".

They seem to want to hide segregation.