I think the issue of slavery has been blown way out of proportion in regard to the civil war. Lincoln himself said he could care less if even one slave was freed, the slavery issue was just thrown in to garner support from the abolitionists (sort of like when democrats use class envy). Lincoln is one of my least favorites in History, he was as bad as oBumma IMO but NOT because of slavery or rights of blacks, of which he could care less (had I been living then I myself would have opposed slavery).... he suspended the constitution and locked up those who opposed him to name a few reasons.
The real issue was the North wanting to cash in on the booming trade and exert (at least some) control over the South... and impose heavy tariffs and taxes.
There were other issues but I feel this was the main one.