“You would not were you born a slave.”
Slavery would have died on the vine anyway, without costing 600,000 lives.
The people who started the war didn't think slavery was going to die on the vine. They saw it as an institution that their children and grandchildren and their great-grandchildren would benefit from. So if the South had won then would you have thought the 600,000 lives were worth it?
Not if the south had anything to say about it.
Perhaps it would have and perhaps it would not have. I saw with my own eyes, cotton being harvested by hand in the 1960s. But going back 100 years before that, the people who were willing to go to war to support their "Peculiar Institution" sure didn't think it would 'die on the vine.'