In this article, Princeton Professor Kwame Anthony Appiah asks an excellent question: "What will future generations condemn us for?"
He comes up with three excellent criteria, too:
First, people have already heard the arguments against the practice. The case against slavery didn't emerge in a blinding moment of moral clarity, for instance; it had been around for centuries.
Second, defenders of the custom tend not to offer moral counterarguments but instead invoke tradition, human nature or necessity. (As in, "We've always had slaves, and how could we grow cotton without them?")
And third, supporters engage in what one might call strategic ignorance, avoiding truths that might force them to face the evils in which they're complicit.
Unfortunately, after this, he wimps out. He gives some good answers, but he misses one. A big one. An enormous, obvious, overwhelmingly loud elephant in the room that you'd have to be blind and deaf to miss.
Care to guess what it is?
(And don't miss the comment section, which seems to indicate that many of the readers have learned nothing at all from the atrocities of history.)