That is two late 20th century historians’ view.
You could find a few people who thought that way in Charleston or New Orleans, but it wasn’t that widespread. Plenty of secessionists, like Senator Wigfall, were more than content with a Confederacy that remained permanently agrarian and supplied cotton to Europe in exchange for manufactured goods. If the South had really wanted more industry, it would have had more industry.
Oh I disagree. There were plenty of Southerners who recognized that industrialization was the way forward. They could hardly have failed to notice it by the mid 19th century. Senator Wigfall’s view was definitely a minority view by that point.
I certainly know better than to take politicians at their word. Nevertheless, Lincoln had never said he had any intention of threatening slavery. Abolitionists routinely got drubbed in election after election in the Northern states. Even if there had been a lot of political support for it, without the consent of the slaveholding states it would have been impossible to get rid of. It takes 3/4s of the states to pass a constitutional amendment and there were 15 states that still had slavery. Ergo, any move to abolish slavery would have required their consent.....ergo, they would have been able to get a generous compensated emancipation scheme as had been done in other countries that abolished slavery at that time to ensure they did not take a huge financial loss....just as the Northern states’ gradual emancipation schemes gave slaveowners in their states ample time to dispose of their slave property to ensure they didn’t take a huge financial loss.
They could be reasonably sure at least for the intermediate term that Northern business interests would remain amenable to slavery considering the enormous profits they were making from servicing goods produced at least in part by slave labor. As I’ve outlined above, had Northern sentiment hardened against slavery, the slaveholding states could have extracted a lot of money via a compensated emancipation scheme in order to get rid of it....which seems only appropriate given that it was Northerners who sold the slaves in the first place making a hefty profit in the process.
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You do realize that saying "I have no purpose, directly or indirectly, to interfere with the institution of slavery in the States where it exists" was not going to satisfy Southern slaveowners.
They believed slavery was a good thing that ought to be spread. They wanted what they thought was their share of the new territories. They wanted to be able to take their slaves with them when they went west. Or even when they went North.
A President who wanted to exclude slavery from the territories was a slap in the face of slaveholders and their pride. They thought it made them second class citizens (as strange as that sounds to sane people now).
There were plenty of ways that a Republican president could "threaten" slavery. He could appoint judges that weren't friendly to slaveowners. He could admit new states without slavery. He could speak up for freedom and allow abolitionist literature the use of the mails. Start debate in Congress on compensated emancipation. Begin a colonization program - or alternatively, start receiving African-Americans at the White House and listening to their concerns.
Plenty of things would threaten the self-image of slave owners and make them feel like it wasn't their country any more. You didn't need a constitutional amendment to make the slave power feel the heat. If you owned slaves, you were used to getting your own way. When you didn't, it would peeve you something terrible.
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Some Northerners brought slaves to the South. But Britons brought more, I believe. So did the French, Dutch, and Spaniards. They were all satisfying the demand.
Then you must have a long list of quotes from other prominent Fire Eaters who thought contrary to Wigfall?