the southern US states prior to the civil war. Imagine Kirk and Spock had come to a planet ruled by (white) land/slave owners who brutalize their (black) slaves. Then, to blend in at a slave auction, they would have put on local clothing and Spock´s line to Kirk would have been "You should make a very convincing slave trader". Would you take that as a joke too?
A resident of a Southern state, I can say that southerners don't confront the legacies of slavery, the Civil War, and susbsequent repression the way that other peoples might look at the dark aspects of their own histories. The strong (though not necessarily dominant) presence of Neo-confederalism soft-pedals the nature of slavery in order to give a Romantic image of the Antebellum south or deny the contemporary existence of racism in politics. (Of course, I also know many Southerners who are very thoughtful on these subjects.)