If you strip the horrors of history from history, the flip side of that is you strip the nobility of rising above such horrors
There's been some discussion lately about the libertarian split over embracing the Lost Cause of the Southern Confederacy and the general Southern attitude to their history. While I'm sure this has been said elsewhere, I think the whitewashing of the horrors of the antebellum South* denies the heroism of the people that resisted those horrors. Rather than downplaying those horrors, the libertarians and more importantly the popular histories of the South could discuss the true underdog Southerners - Harriet Tubman, Frederick Douglass, the white Virginians who tried to abolish slavery in their state in 1851, many others who fought a Lost Cause as underdogs against horrible tyrants. Jefferson Davis, Alexander Stephens, and the others may have become underdogs during the Civil War, but the history of the South before the war didn't put them in that category. If modern Southern schools want to teach a heroic heritage, there's a nobility there that they should emphasize instead.
*And the North also had its own horrors, and its own heroes who fought them.