Pedantic note:

Had things gone the other way many of us would be sitting around and remarking about how fortuitous it was that the South won...

"Fortuitous" means by chance or accidentally. Perhaps you meant that Slag, but I suspect you meant "fortunate".
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The more plausible alternative history isn't one in which the war happened and the South won, but one in which the states in question were allowed to secede, and there was not a war at that point.