A last thought on the moral history of Atlantic slavery, before I move on to something happier.
The history of this subject is so focused on Britain and the United States - and not without reason - that we can lose sight of the wider comparisons. One striking fact from those comparisons which was new to me: in every Atlantic jurisdiction but one, when slavery was abolished, financial compensation of some sort was paid to the slave-holders. They were being deprived of what the law had until then recognised as 'property', and they needed to be compensated.
Which prompts two, contradictory thoughts.
First, while of course you can see why it happened at the time, this is grotesque. Rewarding people for ceasing to commit a terrible crime, well, yes, OK. It's a bit like giving an amnesty to a dictator who agrees to step down: it sticks in the craw, but if it's the price of getting a deal done, there's a case for it. But the implication that slavery was legitimate - that, in fact, all that has happened is that the state has used compulsory-purchase to acquire the slaves and then to free them - that's not very nice.
I can see an excellent case for compensation being paid when slavery was abolished. But not to the enslavers, for pity's sake! And the fact remains: neither enslaved people nor their descendants have been compensated in any jurisdiction for the awful crimes that were committed against them. And we all know that those crimes' after-effects are still being felt across the whole Atlantic world.
Who should pay? Perhaps, at the least, the inheritors of those who were paid compensation.
... But second. There was one case where no compensation was paid: the United States, where slavery was ended by war and by a dictated peace, in which slave-holders did not need to be appeased. America did not pay in money to free its slaves, it paid in blood. As Lincoln said, 'every drop of blood drawn with the lash shall be paid by another drawn with the sword', which is certainly more stirring and virtuous than paying the South off would have been.
But was it better? I don't know. If compensating slave-holders has a merit, it's this: the slave-holder who takes the money has consented, indeed bought into the new system. The white South, by contrast, took a century to accept the terms of the peace imposed on it in 1865. And since it couldn't be subject to indefinite military occupation, that meant that it quickly reverted to something which, while it wasn't slavery as such, wasn't exactly freedom either.
It couldn't have been any other way, of course. The South would never have accepted a deal to pay it for abolishing slavery, at least not until the North was in no mood to pay and had no need to. But in retrospect, almost anything that could have drawn some of the racial poison which still flows through America's veins would have been worth it.