That has never been my argument. For the last three years, i've been pointing out that what was at stake was the bulk of European trade, and the possibility of the South capitalizing industry (with the extra money) that would compete directly with established Northern Robber Barons.
The dispute was on whether New York would continue being the seat of Empire, or whether it would fall to Southern economic challengers.
If the South had been left alone, very wealthy people in the North East were going to lose huge sums of money, and possibly even their businesses altogether. More than enough motive to bring down the fire.
Yet in one of your earliest posts to me on this thread you stated that Sourherners were taxed at 12 times the rate of Northerners per capita, although you never explained by what mechanism that was possible. The only federal taxes at the time were tariffs. Why did you bring up tariffs? Apparently to show the fabulous riches the North would lose, although exports were only 9% of total economic activity.
Since it was the Southern states that seceded, and not the North, what was their reason to do so? Northern control of the Southern economy? Was it their fault Southerners didn’t want to build factories, mills, and railroads?
You seem to be fixated on the chimera of economic competition between North and South, without really explaining how that actually motivated Southern secession in 1860. Why not 1850? Also, why the sesech didn’t mention it at the time.