Ultimately, Piepmeier says we should make it easier for women to bring children into the world. Bully for that. But the fact that “the world is a difficult place” for some people more than others is a problem unsolvable by social and political reform or medicine. How much poorer, how much more pre-disposed to a disease, how much more socially detested does one have to be to be beneath this eugenic hurdle for existence?

All the ingredients still exist for a more explicit return to eugenics in our culture and politics: inequality, fear, detestation of the other. But if it comes back, it is unlikely to come in the explicitly racialist terms of the biodiversity-obsessed right. Liberal societies have the antibodies against that.

Instead, it will come to us in terms of “quality of life,” and “health and safety.” We will be urged that every child deserves the best society can grant, and stigmatize those for whom “the world is a difficult place.” And thereby we legitimize the destruction of those who would merely “live” in society rather than thrive in it.