Im not sure America gained from slavery in the long run. The economic cost of the civil war, the destruction of the South, and the countless dead were probably a net negative over what was gain from slavery.

America achieved massive wealth in spite of a violent history, not because of it.

The working class is living better than at any other time in history. Without progress they'd all be working fields, with little to no leisure time, with little in the way of education, entertainment and the arts. They'd be worried about famines and diseases that have long been brought under control.

Life back then was short, nasty and brutish. If the population continued to grow with corresponding progress, we'd be fighting even more over the limited resources available.

> The working class is living better than at any other time in history

On the larger scale of history, yes. I don't think working class people are necessarily doing better than a few decades ago, when they had stronger unions and more power, and before wages stopped rising (which seems likely related to the loss of power).

But an important note, and I don't mean to pick on the parent. In these discussions, the working class is almost always described as "they" and not "we". What do we really know? Input from people with real experience is necessary.