Remember what came just AFTER 1865.
Monopolies.
It's pretty cynical to assert that the entire Federal government was motivated to invade the South at huge cost in blood and treasure to protect the interests of Northern Oligarchs expanding into the West.
It implies that the Government of 1860 was for sale. I'd rather not believe that, though the evidence for our Modern government being for sale is getting harder and harder to shake every year.
While prophesying the War over a decade early, it may suggest some good arguments for you. It certainly attests to some of the things that the Virginia gentry considered significant in the growing apart that was taking place in the pre-conflict era.
“It’s pretty cynical to assert . .”
Don’t go there. The only thing our puritanical northern friends ever wanted to do was go to the chapel and pray. And the only evil was in the South where people grew food and fiber and raced horses.
Grant’s Tea Pot dome comes to mind.
Look at Lincoln’s cabinet. Oligarchs with pure lust for power, competition with Lincoln, and eyes on Western development.
Chase
Seward
Stanton
http://www.mrlincolnandfriends.org/inside.asp?pageID=7&subjectID=7
This is why I look at the Civil War as THE power play for federal-and oligarchical-control of US development. Steel magnates, rail magnates, the lot of them, came out winners. If you look, you see that the transportation-canals and rail lines-went their way only. Small farmers and resource-rich land that had been settled were almost entirely ignored.
Yes, slavery was involved. I look, however, to the Missouri Compromise as the bellweather. That vote had to foretell which way the country would go from then on, and that there would be NO MORE COMPROMISE.
New England and its magnates won, and so we have that ethos in American politics to this day.