For the record, there actually was never a civil war where one side fought for the right to own white people under the banner of a "black power" flag. Also, there is not to this day (nor was there ever) a state that still flies that flag of white oppression.
For the record. the Civil War was not about one side fighting for the right to own black people under the banner of a "white power" flag, either.
The slavery issue was used in recruiting, convincing normally anti-war religious factions to drop their opposition (or even support it) under the "just war" doctrine, and eventually as a tactic near the end of the war to try to promote a slave revolt in the Confederacy. But the original fight (like the American Revolution, the "occupy" movement, and the RIAA/MPAA inspired draconian copyright regime) was about a crony capitalists / government axis using tariffs and laws to keep a large segment of the population as captive customers for overpriced monopoly products, suppressing both their trade with suppliers in other countries and their ability to make their own, lower-priced, replacement products.
It was the north's "1%" against the south-as-ghetto.
(Note that I say this as a descendant of a number of people who fought on the Union side.)
Unfortunately, the actual history of the conflict has been largely suppressed. IMHO the current anti-confederate-battle-flag move is both an attempt to finish off the suppression of the history of the conflict and to pre-emptively propagandize against any move by southern border states to take their own measures against what they perceive as a massive invasion across the southern border.
"Those who don't study history are doomed to repeat it." applies here - even if the history isn't studied because books about it are suppressed (e.g. removed from book stores and libraries because they contain the "evil racist flag").