So, what's next? Will this debate subside or continue, as people look to other uses of Confederate icons and symbols? Is this simply about a flag tha… - Brooks D. Simpson

In 1864, black Union troops were involved in operations against Lee's army outside Richmond and Petersburg, and some of them are taken prisoner. Lee puts them to work on Confederate entrenchments that are in Union free-fire zones. When Grant gets wind of this, he threatens to put Confederate prisoners to work on Union entrenchments under Confederate fire unless Lee pulls out. So Grant was willing to embrace an eye-for-an-eye, tooth-for-a-tooth retaliation policy based upon Confederate treatment of black prisoners. For Grant, it was the color of the uniform, not the skin, that mattered.

White southerners saw Lincoln as anti-slavery and his election as a direct threat to the survival of the peculiar institution. Are you going to tell me that they were stupid or deluded? Is that any way for white southerners to honor their ancestors, by ridiculing their intelligence? Indeed, Stephen Douglas' decision to accuse Lincoln of embracing racial equality tells us that playing the race, or racism, card in the 1850s was alive and well, because Douglas believed that he would gain political traction among racist Illinois voters, who were white, after all, by associating Lincoln with the cause of black equality. Lincoln's response was thus also an issue of political survival. So was his decision not to publicize his support for limited black suffrage in Louisiana in 1864. He advanced the idea in a private letter, but waited thirteen months until he made his sentiment public, and three days after he made that sentiment public, he fell victim to an assassin's bullet because that assassin could not bear the thought of black equality. Lincoln knew he lived in a racist America, North and South.

Ranting about "political correctness" is best read as "I can't really deal with the merits of your interpretation, so I'll deride it largely because it doesn't reinforce my own preferences and prejudices."