Ok, first of all, the Confederacy was never a separate nation. The Union was called that because it was intent on keeping the union together. And yes, I agree that no wars are fought over only one thing, although nearly all wars are predominantly economic, with most of the other issues being secondary. I’m curious, what are the other eight reasons for the Civil War?
No, I do not want to contemplate a time when humans might overtly and socially acceptably own other humans again.
The book you’ve referenced is just more Cult of the Lost Cause. Here’s what the American Civil War Museum has to say about what Confederate leaders said at the time:
“Although they were the proximate cause of conflict, Constitutional principle and secession were not the ultimate cause of the War. To identify that ultimate cause, we must examine the words of those who led the secessionist movement.
In 1894, legendary Confederate partisan leader, Col. John S. Mosby expressed surprise at a recent speech in which the orator dismissed “the charge that the South went to war for slavery” as a “‘slanderous accusation.’” “I always understood that we went to War on account of the thing we quarreled with the North about,” Mosby observed. “I never heard of any other cause of quarrel than slavery.”
In contrast to the post-war efforts to downplay the importance of slavery, it dominated the thinking and the rhetoric of southern statesmen in 1860–1861. Deep South states sent commissioners to the Upper South states to persuade them to leave the Union. Their arguments emphasized the mortal danger that the recent election of Republican Abraham Lincoln as president posed to slavery and to white people in the South. The formal explanations that several states issued to justify secession similarly emphasized slavery. (For these sources, please see the related links accompanying this entry.) Even Virginia, which seceded after war began, had formulated a list of demands that the U.S. government must meet if Virginia were to remain in the Union; all of them related to slavery and race.
Typically, Mississippi’s November 30, 1860 resolutions — passed in response to Lincoln’s election — began with a strong defense of state sovereignty and rights, but moved quickly to a reminder of the original Constitutional guarantees of slavery and the northern states’ violations of those guarantees. Ironically, southerners were insisting on the enforcement of Federal fugitive slave laws against northern assertion of their “states’ rights.”
Defense of “states’ rights,” southern “honor” (that is, an intense resentment of perceived northern criticism and condescension), fear of Federal “coercion,” and a growing belief that the South and North were divergent civilizations all factored into the decision making of southern statesmen in 1860–1861. But it was not those abstract motives that prompted secession and led to war. The South’s defense of the very real institution of slavery and of the economy, society, culture, and civilization built upon slavery was the indispensable factor that led to war (emphasis mine).