Everyone points to those speeches and documents, brought by the Southern societal elite and conclude it was only about slavery, dismissing all the other evidence that points to freedom to make their own choices; which slavery just happened to be the immediate point of contention.
It is ridiculous to think that tens of thousands of men would force march to battle to fight for something they had no share in.
If it wasn’t slavery, it could have been something else; chiefly that the north and south were two different peoples that didn’t have a lot in common.
“ Everyone points to those speeches and documents, brought by the Southern societal elite and conclude it was only about slavery, …”
Everyone, including the southerners writing the secession declarations in Georgia, Virginia, Mississippi, Texas, and the one that got the party started, South Carolina.