This is Civil War 101 stuff.
The fire-eaters worked themselves up into a frenzy telling each other that Lincoln would take slavery away from them. That is why they up n skedaddled. Or so they told us.
Even DoodleDawg knows that possibility was not even remotely true.
I've done the math. If the 11 states that became the Confederacy all voted to keep slavery, it would take 44 states in the Union for them to be outvoted by the remainder. (Wasn't possible till 1896) If the Union slave states also voted against abolishing slavery, it would have taken a Union with 60 states to outvote the slave states.
On top of that, Lincoln said repeatedly that he would not attempt to do anything about slavery, and that he actually didn't have the power to do anything about it even if he wanted to.
So it sounds like "Civil War 101" is not at all compatible with the demonstrable facts of that time period.
Or so they told us.
I have read many opinions to the effect that this was indeed what they said, but it was intended as subterfuge for their real reasons, which was economic independence.
At least this is what one Northern newspaper believed.
The Boston Transcript, March 18, 1861:
"the mask has been thrown off and it is apparent that the people of the principal seceding states are now for commercial independence. They dream that the centres of traffic can be changed from Northern to Southern ports..."