My gut feeling is with the North, because most of the historical Americans I like best - the writers, especially - are Yankees.
I have spent periods in New England and in Texas - and much preferred New England (although I liked the hospitality and manners of the Texans) - indeed I have a love for the physical place of New England, its history and architecture; which probably exceeds that of anywhere outside my native land.
It may also be a factor that the US climate and scenery outside of Greater New England (i.e. including Upstate New York) is, mostly, alien and more-or-less unpleasant to me - it would be too hot, cold, dry or humid; and often on too large and inhuman a scale for me.
My impression is that in the American Civil War, both sides were in the wrong; and the war did far more harm than good - it was a war that should not have happened, it was not a 'just war' from either perspective.