I think promoting reconcilable issues such as tariffs and shipping to primary importance in the civil war, while ignoring the 6000lb elephant in the room is a stretch.
All wars are about money and control as you say. Slavery and the disparate N/S economies created a host of divergent interests. In the 1858 House Divided Speech, Lincoln campaigned to "arrest the further spread of it, and place it where the public mind shall rest in the belief that it is in the course of ultimate extinction". He wasn’t talking about tariff opposition. But Southern economic interests and culture demanded more protection of slavery than that.
"That’s when the South seceded, setting up a new government. Their constitution was nearly identical to the US. Constitution except that it outlawed protectionist tariffs, business handouts and mandated a two-thirds majority vote for all spending measures… " … and enacted constitutional protection of slavery, over any potential objection under states rights to eliminate it within their boundaries.
The VP of the confederacy said slavery was the "cornerstone of the Confederacy" upon succession, but changed his mind and claimed the war was about “states rights” after their defeat. This really isn’t difficult to see through. As wars go, that one really was that simple.
Not that simple. The issue of states rights raised strong impediments to the efficient conduct of the war. Davis wanted a more centralized control, but Stephens and others were opposed to this, including many governors. One reason why the North won was central command. . Lincoln had wanted to convey such authority on Halleck, but Halleck could not or world not. But in Grant he found his generalissimo. Lee never had such authority.
I beg to differ, nothing is ever all that simple.