It made the southern states more prosperous… IF you exclude black people from the definition of people, which is what slavery did.

Pretty sure the south lost because of the 3:1 soldier advantage, and besides Lee the North had all the best military leaders and experience. Some say the industrial output of the north mattered more, but truth is the south had plenty of weapons but no people to use them.

There’s certainly debate about that. And that’s the exact discussion you want to see occuring as that’s what teaches critical thinking.

So yes, you should be discussing the beneficial aspects of slavery.