> Plantation owners in the south at the peak of slavery had Bezos-esque wealth. Although the proles in the confederacy were poor compared to their counterparts in the north (especially slaves; that's obvious!), the south was wealthier in absolute terms.

The south was a plutocracy, which made a few individuals very rich, but it was not richer than the north in the aggregate. The claim is trivial to assess: slavery was ended in a dramatic fashion, so you can compare the country's wealth before and after emancipation. It did not change: https://www.econlib.org/archives/2014/09/ending_slavery.html.

The notion that the antebellum south was "rich" depends on a slight-of-hand. It counts enslaved people in the south as "wealth" but free people in the north as "labor." But that is non-sensical: a society wouldn't become vastly richer if you enslaved half the population overnight. Likewise, you can't compare the "wealth" of the north and south by treating labor in the south as "wealth" but not in the north. As you can see in the chart, even treating enslaved people as capital stock, the civil war did not reduce America's wealth. And if you correctly classify enslaved people as labor, you'll see that ending slavery led to a rapid increase in the south's capital stock. That's because, as basic economics predicts, an unfree labor market is actually bad for the economy.

Some of the recent articles floating around about the "economics of slavery" are not by economists and are rife with conceptual errors. I'll make on basic observation. In condemning colonialism, people assert that Britain made India poor by limiting it to supplying cotton (a commodity) while British factories performed the lucrative textile manufacturing. That left Indians low on the supply chain, and forced Indian consumers to buy finished goods from Britain. But for the exact same reason, exporting cotton could not have made the south rich. The opposite is true: the slave-based cotton economy kept the south from moving up the supply chain, and kept it poorer than it would have been otherwise.

I’m not an economist and have a hard time following the most complex arguments relating different means to measure wealth etc but by reading your comment two things came to mind. If you slave all the working population in a country you will could position that the overall wealth did not change, ok I get the point. But what about wages? You’re effectively appropriating a non insignificant amount of money and transferring it elsewhere. Some people are effectively getting wealthier. Which relates to the second thought, you say slavery was capping the growth of the south. But only if you measure the overall economy? Effectively for big plantation owners it did not necessarily mean less wealth? More than happy to understand the finer points of your argument since I’m probably missing an obvious concept known to economists that scapes me

You're correct. The plantation owners were benefitting, and that made them wealthier. But that came at the expense of the rest of the economy. Those plantation owners, likewise, lost wealth when slavery ended. But the rest of the economy grew.

The distinction is relevant to the political debate around why all this matters. Labor was expropriated from slaves, and that enriched plantation owners, there is no doubt about that. But some people want to go a step further, and say that America owes its overall prosperity to slavery. Except insofar as you can trace wealth to certain slaveholder plantation fortunes, that assertion probably isn't true.

Enslaved people are property which is the whole point. You can't sell worker to get money for project nor use him/her for collateral for mortgages. You can do both with slaves.

It is not proper to classify slaves as labor.