My Sunday column tried to take the ongoing debate over marriage and upward mobility in a slightly different direction, by prodding social liberals to acknowledge the ways in which their own ideological vision and its victories – legal and cultural both – have played a role in the married, two-parent family’s decline. I don’t think my argument has won many converts, but rather than respond to the responses right now I wanted to highlight one of the arguments that inspired the column in the first place: This essay from Steve Randy Waldman, which makes the case that “marriage promotion” as...