LS, He considers Marylanders, West Virginians, Delawareans, Kentuckians and Missourians as Southerners even though none of these states ever were really part of the Confederacy - because these states were culturally part of the South.
And part of his larger argument, which tends to be obscured, is that following myth:
"The people of the North were united as one against the slave power/The people of the South were united as one against the Yankees"
is a myth that serves the worst elements on both sides.
It serves the anti-Southerners who want to tar the entire Southern people with Confederate ideology, and it serves the anti-Northerners who want to portray the North as cultural imperialists.
The reality is that in both Union and Confederacy there were sizable elements of the population who were not on board with their government's goals.
You got that right. There were “Copperheads” and all sorts of northern Dems who opposed the war, including George McClellan by 1864. Victor Hanson makes a nice point in a speech about how it depends on which year it was how “great” or “brilliant” Lincoln was. Right after Fredericksburg, a much higher % of northerners were “anti-war,” and after Gettysburg, a much higher were “pro-war.”
It serves the anti-Southerners who want to tar the entire Southern people with Confederate ideology, and it serves the anti-Northerners who want to portray the North as cultural imperialists.
That's why learning the true facts can be so important. Then the Civil War becomes a poor vehicle for regional chauvinism. Get that out of the way, we can argue over more relevant differences such as grits and auto racing.