Which in turn suggests the reason that reparations can be appropriate between nations, and disastrous within them. Germany can offer Israel money in partial recompense for the wrongs of the Holocaust, because Germany and Israel are two independent entities. For the United States to do the same for the descendants of slaves would be to imply that afterward, we will be going our separate ways, with no special obligations on either side. And indeed, conservatives can sometimes be heard tepidly endorsing reparations in just this sense: a one-time payment, and then nothing more owed — no affirmative action, no “national conversation on race,” nothing.

That is the only conception of reparations that could possibly be politically viable. It would also be utterly toxic, ultimately widening divisions that we’re trying to shrink. And the benefit is likely to be smaller than the heroic price tag suggests; the economic evidence from lotteries suggests that one-time capital transfers do very little to improve the long-term welfare of recipients.