You should also consider the fact that only a very small proportion of white Southerners of the Civil War period owned slaves ... but a very large percentage fought against the invaders. (And black Southerners included not only slaves, but free black slave-owners, and both slave and free black Confederate soldiers!)
Real history is always more complicated than sound-bite ideology. The nobility of General Lee is beyond the details of history. He was a truly saintly man, and I say that as a Catholic :-). We consider General Lee and General Jackson the "patron saints" of our home school, and we firmly believe they are in Heaven praying for us.
Very nice words indeed.
The fact that only a small percentage of Southerners owned slaves helped seal the doom of the CSA. The South was not united behind the Confederacy. Many people had no desire to fight for what they saw as the slave oligarchy's interests. Almost 20% of Southern soldiers in the war fought in the Union army. And many soldiers in the Confederate army had Union sympathies but were caught in the draft and forced to fight against their convictions. This contributed to the disintegration of the Confederate army and the CSA itself.