A sticky wicket

Everyone KNOWS the American Civil War was about slavery.  Right?

Kinda.

Slavery was a component, but it had a lot more to do with the northern states telling the southern states what they were going to do about slavery than the actual slavery itself.

Maneuvering about how new territories were to decide whether slavery would be legal there or not had a lot to do with it as well.  There was a real concern that the new territories would become states and then simply outvote the slave states on the matter.  Massachusetts splitting Maine off as its own state just to get (prevent the slave states from getting one up really) more abolition votes reinforced the position.

Pressure was maintained on the issue until the southern states felt they had literally nothing to lose and everything to gain by leaving.  They felt they had no options besides the path taken to have any chance at all at deciding their own fate.

If only the thing that we were talking about wasn't the horrible institution of chattel slavery.

But there's also things like messing with the price of cotton through tariffs and export restrictions.

Things like Texas that had only just left Mexico over the very matter of self-determination.

Things like Florida having quite recently being Spain and not liking the return of the dictatorial air from afar.

The war wasn't really about slavery to the everyday soldier until the emancipation proclamation.  To the Union it was about preserving the union; to the Confederates it was about deciding how (and by whom) they would be governed at a national level.

Slavery was dying on its own too.  Advances in agricultural technology were making it obsolete.  The Jim Crow version of slavery (sharecropping) didn't survive the technological advances either.  Brazil is a good proof of how slavery died in western civilization.

While we're talking about how evil slavery is, we should also consider the working conditions of an immigrant worker in a factory in, say, Pittsburg or New York City.  Some of those bog-Irish might have considered a slave's "lifestyle" to be a step up.