It's in the Atlantic and it's called "Why do so few blacks study the civil war?"
It rejects the idea that the war was a tragedy; that is was a result of a failure to compromise, or of misunderstandings, the romanticizing of the gentlemanly southern generals.
For African Americans, war commenced not in 1861, but in 1661, when the Virginia Colony began passing America’s first black codes, the charter documents of a slave society that rendered blacks a permanent servile class and whites a mass aristocracy. They were also a declaration of war.
The final part of Charles Mann's excellent 1493 gives a good overview of the war between Europeans and slaves fought across the Americas.