And as several Northern Newspapers and Sherman himself pointed out in his letter to his brother, the smuggling of goods subject to only a low tariff in the South would be rife. The remaining states in the US would then have to try to set up custom houses along the Mississippi river (good luck with that) but it would be futile. The North would lose out on the servicing of cash crops, would lose out on the tariff revenue overwhelmingly used to pay for corporate subsidies and infrastructure projects in the North, and their manufacturers would be undercut on price by goods brought into the South. They would have to radically slash their tariffs and to even try to compete on price for manufactured goods. The Southern states were a cash cow for them.....a captive market and large source of jobs and profits for them.
I've made this point before. At risk were midwestern markets for Northern manufacturers. With the South setting up trade on the Mississippi, European products would flood the Midwest, costing the industrialists in the North their markets and their riches.
Ditto just doesn't understand that the Northern industrialists were not stupid and not squeamish. They knew exactly how great of a threat an independent South represented to their financial future, and they used every bit of influence they had with the newly elected President to push for war to stop it.
But some people try to minimize the economic threat the South posed to these industrialists by calling it a dispute over "tariffs."
No, it was way bigger than "tariffs."