I think we have a winner in this week's longest sentence competition.
What you're doing is stacking the deck or creating a "straw man." You keep flailing away at this image that you've created and count yourself a winner in the argument, even though your straw man is far from "the primary moral argument we've been discussing." It's your preoccupation, and that of your friends, more than anyone else's.
You use the idea of disproving some hoary old myth to create a new one. Or simply replace one supposed tired old myth with another. People coming along now, who may never have been exposed to the myth you claim to be attacking, eventually come to accept your own myth of Yankee hypocrisy and venality and savagery as gospel, and it becomes as entrenched, and as false, as anything you object to.
A lot of bad history takes root as supposed debunking, and soon needs to be debunked itself. People sell and even get rich by simplifying and distorting what historians say to the point of parody, and then hawking their own simplistic and distorted views as the suppressed truth behind the official story. It's a racket that a lot of people have tried to get into.
If you really want to get beyond myths, you're going about it in the wrong way. Recognize first what we are as human beings and as Americans, and go beyond us vs. them, to get at that capacity for good or evil in all of us. Don't simply try to reverse the positives and negatives in the version that offends you to produce a photographic negative, that's just as biased only with the colors reversed.
And how is your "primary moral argument" distinguishable from this Mark-of-Cain ridden Southern Beast I described, whose immobilization before the Triumphant Forces of Righteousness is the entire purpose of your "primary moral argument"?
You argue Southerners are endogamously bad -- or maybe only culturally polluted by their mothers' milk -- in order to obtain and justify a social sanction to reform them by force, against their will, like cigarette smokers, into "New South" Yankee-Men/Soviet Men, whatever. Let's start there.
Your moral injunctions are actually a claim -- a claim of the right to lobotomize and brainwash. Admit it.