The assault on American history continues apace, with the further removal of Confederate monuments and symbols, and the expunging of anything relating to slavery or slaveholders. Mounting any defense against this cultural warfare has been next to impossible, because it would seem to demand justifying slavery. The same considerations prohibit any criticism of the Union cause in the Civil War, with all the horrendous violence and destruction of that conflict. If not desirable, this purgative violence was essential, and unavoidable.
Let me explain why we need to treat that view very skeptically indeed.
Most current historians of the era hold that slavery was so profitable and pervasive in Southern society that it was never going to go away of its own accord. The only way to finish it off was by force, and ultimately, that meant bringing on a war that killed some 750,000 Americans. To put that number in context, the United States in those four years lost about twice as many dead as have perished in the Syrian conflict (2011-). Given the relative population of the two societies then and now, the deathrate was comparable.
But an excellent case can be made that the war was unnecessary, not of course because slavery was in any way defensible, but because the slavery institution would have ended without military intervention. And ended quite soon, within a decade or two after...