Something that doesn't seem to be getting through to you is the fact they didn't have to fight to keep blacks in bondage. Lincoln and the Northern Republicans were *GIVING* it to them.
Permanent USA slavery is what Lincoln and his cohorts offered them. All they had to do was take the deal.
So spare us the moral outrage. Your side offered permanent bondage. Your side was *NOT* the good guys.
Permanent USA slavery
No. The Corwin Amendment only limited the action of the U.S. Government. Any state in the Union could abolish slavery as it saw fit.