If you are going to seriously argue that it was, and rightly should have been "constitutional" to hold slaves in the South, but "unconstitutional" to free runaway slaves in the North, and that the Supreme Court's Dred Scott decision was a good one, then I'd suggest you don't belong on Free Republic.
Go post your lunacies where they belong: on Aryan Nation, or some Neo-Nazi site.
The correct answer here is that slavery had to be defeated, period, and that the South's refusal to accept this in any form was the cause and motivation for the Civil War.
Getting despirate, eh? That's the first insult of that kind to me in my long years of posting here. I argue history. You insult.