The poorer states in the country were poor long before the "Solid South" broke up and turned Republican.

Yes, but the culture adopted can extend being poor, or it can help the economy. The South and Appalachia still have cultures that don't value industriousness or education generally. They aren't known for it. So when the coal or cotton goes away, the culture extends being poor.

My point is that the culture makes more of a difference than we think. If you have a natural asset like oil, investment will come into the area. When the asset is depleted, the economy slows way down.

The South's culture seems to extend being poor. Same with Appalachia's, but it also has geography problems. The West can only support so much in the high desert, high suicide areas. None of those cultures values education, but the West has some areas that value industriousness.