History after the Civil War seems equally compelling as history before the Civil War in regard to this issue to me. If the South were truly a region with no race problems except those caused by meddling Yankees, why was the aftermath of the war a failed Reconstruction, the establishment of the Ku Klux Klan, lynching as an entertaining pastime, Jim Crow and violent opposition when integration became law? It seems to me those are the behaviors of a people with deep racial problems, not of folks who never had anything against blacks and fought a war over something other than maintaining slavery, as the neo-Confederates claim. I believe the history of the South is that of a region conceived in white supremacy and still enmeshed in it.
In summary, the claim the Civil War was not fought over slavery is false. But for the Southern oligarchy's perceived need to protect the peculiar institution, the war would not have occurred. The denials of modern neo-Confederates are lies meant to mislead the uninformed. They are mired in nostalgia for the past and hope of returning the country to it.
Note: I've read all three of these books and recommend them without reservation. If you can afford to purchase only one of them for now, my suggestion is Slaves in the Family, a splendid, award-winning history of life in the South before and after the Civil War. Its author, Andrew Ball, is a descendant of a South Carolina family that owned more than 4,000 slaves and more than a dozen plantations. He is as far from being a neo-Confederate as a person can get.