Where I cannot acquiesce is in the causation.
The states of SC & Georgia sent out what were called "Commissioners" to lobby the state legislations of the remaining Southern states that would eventually make up the Confederacy. The speeches and letters they wrote clearly laid out the preservation of slavery as the main cause for secession.
The Deceleration's of Secession from the Confederate States all lay out, in no uncertain terms, the reason for secession was slavery.
The debate on the motivations of the individual soldier bother me only insofar as they are extrapolated as an acquittal and denial of the actual cause of the war on a larger scale. I realize the average soldier, on both sides, did not fight over slaves directly. Nevertheless, that was the reason they were forced to pick up arms to defend their other reasons.
My opinion is that the conflict was an artificial creation largely produced by the slave owning class to further their own narrow interests. Yes, there was a manufacturing interest in the northeast, but I don't think there was real conflict between the bulk of the peoples of north and south. Generally, the people of the north and south had more in common with each other than they did with the powerful economic interests of their own regions that had the greatest stakes in the war.