Or it could be that what they wanted was to run their own affairs without sending 40% of their export revenue to New York, and God only knows how much of the rest to Washington DC. Always left out of these discussions is the fact that these two cities were collecting *MOST* of the money produced by the South. Same two f***ing cities that are still trying to control the rest of us today.
This is exactly what it was about all along. Northern Newspapers were full of editorials saying that if the Southern states became independent they would prosper and the North would lose out financially on a massive scale. The South was generating the vast majority of the exports and paying the vast majority of the taxes. That's to say nothing of the shipping, banking, insurance and import/export business and all the salaries and commissions generated from them.
This aspect only tells part of the story. The financial risk to the great Northern Industrial barons was much greater still. By becoming independent, US Protectionist laws no longer applied, and the South could import as many European manufactured goods as they desired, and this would directly impact sales of Northern goods to the South.
But Wait! It would not only cause them massive loss of sales to the South, Southern companies could import these goods and distribute them through the Mississippi river watershed to huge swaths of the Midwest, and they could also distribute goods all along their borders to the Northern states. Another massive financial impact to the same Industrial barons of the North.
But Wait! Profits made by Southern corporations would not only ramp up Southern shipping, it would attract Northern experts to move south and set up manufacturing facilities in Southern cities, which would then also compete directly against the Northern industrial barons.
But Wait! Over time, states realizing that their financial interests were better served by the Confederacy than by the New York controlled Northern coalition, would eventually chose to join the Confederacy, starting with all the border states. Over time, the Confederacy would grow at the expense of the Union.
The businessmen of the Northern industries were nobody's fools. They could see the threat to their power and control, and they certainly wanted none of it, and the simplest way to stop it was to go to war with the South, blockade all their trade, and smash this upstart government that would threaten their money streams.
And so the war was about Money and Power, but they did everything they could to convince naive people that it was about the "milk of human kindness", and gullible people bought it and still repeat this nonsense today!
You would think that people could grasp that when Lincoln offered them effectively permanent protection for slavery through the Corwin Amendment, that slavery wasn't what either the North or South really cared about. But some people are just dense when it comes to seeing things as they truly are.