"...the idea that the Confederacy was a heroic institution not centered on the principle of slavery but rather unfairly attacked by Northern aggressors."

All it would take for any reasonably intelligent person would be to read the cornerstone speech of the CONFEDERACY, given by the existing vice president of the confederacy, where the basis for succession is made very clear:

"[I]ts foundations are laid, its cornerstone rests upon the great truth, that the negro is not equal to the white man; that slavery—subordination to the superior race—is his natural condition. This, our new government, is the first, in the history of the world, based upon this great physical, philosophical, and moral truth."

https://en.wikipedia.org/wiki/Cornerstone_Speech

And as far as the Republican party being "the party of Lincoln", it seems more than a bit strange that the direct descendants of the confederacy elected barely a single Republican in the next 100 years.

Great stuff. Thank you.