With hind site we can parse this a lot better than the ones living it at the time, but my thinking that the reason the South was giving slavery so much importance in the beginning was the fact that they wanted to make sure that the Status Quo was maintained. You have to remember that that that time Slavery was legal. Abolitionist were trying to end it but Lincoln was not. New States coming in that were not slave states, nor given the choice themselves was a danger in the power struggle as the South saw it. The was was about States Rights with Slavery being one of those rights, maybe the most important one, because New States were being denied the choice. The big plantation owners had the money and time to be involved in politics, so their ideas are the ones that were immortalized in history, but the poorer, common man that owned no slaves fought the war. This shows that important as it was, it was not all about slavery. At least to me. miles
