I'm afraid I'll have to disagree with you here.
The CSA constitution explicitly preserved slavery in the South. Here are a few examples, with some emphasis added:
"No bill of attainder, ex post facto law,
or law denying or impairing the right of property in negro slaves shall be passed."
Article IV Section 2 of the CSA constitution added language about slavery.
In fact, a lot of language was changed to protect slavery. Even the sections regarding taxes on industrial products is designed to protect slavery.
At Alabama's secesion convention, G.T. Yelverton said "The question of Slavery is the rock upon which the Old Government split: it is the cause of secession."
Robert Hardy Smith (also from Alabama) said,
I congratulate the country that the strife has been put to rest forever, and that American slavery is to stand before the world as it is, and on its own merits. We have now placed our domestic institution, and secured its rights unmistakably, in the Constitution. We have sought by no euphony to hide its name. We have called our negroes 'slaves', and we have recognized and protected them as persons and our rights to them as property.
South Carolina congressman Laurence M. Keitt said in January 1860, "The anti-slavery party contends that slavery is wrong in itself, and the Government is a consolidated national democracy. We of the South contend that slavery is right..."
In December that same year, he said, "Our people have come to this on the question of slavery" during the secession convention.
South Carolina's secession ordinance said that the main reason for leaving was, "...increasing hostility on the part of the non-slaveholding States to the Institution of Slavery...."
I could go on here, but I feel I've made my point.