Your analogy is fatally flawed. Any person or state who revolted against the Soviet rule exercised their natural law right of revolution form intolerable oppression.
The same cannot be said for the southern insurrectionists of the 1860's. There was no oppression. There was no threat of oppression.
"Now which is it, a few CSA "buffoons" or an entire generation that was responsible for the great crime of self determination?"
The buffoons in the leadership are culpable. Their followers paid the price.