After President-elect Donald Trump's recent victory, some of his supporters celebrated by flying Confederate battle flags from pickup trucks and waving them at rallies.

But Trump's victory may mark the resurgence of the Old South in another more sinister way: The return of "racial amnesia." 

That's what some historians are saying as they watch a familiar storyline emerge. Trump's triumph is now being roundly described as a revolt by white working-class voters; racism, sexism and religious bigotry had little, if anything, to do with it.

People making this argument are following a script first honed by another group of Americans who made history disappear. After the Civil War, "Lost Cause" propagandists from the Confederacy argued the war wasn't fought over slavery -- it was a constitutional clash over state's rights, they said; hatred toward blacks had nothing to do with it.