The father of a fallen soldier intends to keep reminding Paul Ryan about this, to keep insisting that it is a moral failure, until Ryan changes his mind. As Josh Barro put it, the Mexican American jurist, Gonzalo Curiel, “is a sitting judge presiding over a Trump case, so he couldn’t camp out on TV and keep the story alive. Khizr Khan can.”

That will have consequences.

Before, Republicans could always maintain, with at least some veneer of plausibility, that they would of course repudiate a politician who crossed a certain line.

With Donald Trump as their standard-bearer, that line has been shown to encompass a candidate who, feeling attacked by the father of a fallen soldier, finds that his first instinct is to lash out at the man’s grieving wife, the fallen soldier’s mother, impugning both with ignorant, derogatory speculation rooted in prejudice.