It was not by accident that the North, where slavery was not prevalent and was largely abolished by 1820, was the focus of the American Industrial Revolution. England, the first nation to experience the Industrial Revolution in Europe, had abolished serfdom before the rest of Europe.
Good points about slavery. If the Romans had ever figured out that they needed an orderly system of succession, and that generally the political classes were their own worst enemy, the Empire might never have fallen. Good thing though for all of us that it did, else none of us would ever have been born. :^)