The story of Donald Trump’s call for a database, or some sort of national registry, of Muslims in the United States consumed much of the political conversation Thursday and Friday. “Trump says he would ‘absolutely’ implement Muslim database” was the headline of an AP story Friday. In short order, critics were bringing up Nazi Germany to condemn Trump’s purported proposal.

What was happening? Just to be clear right from the start, a national Muslim database seems blatantly unconstitutional, although there are terror watch lists and the FBI and other agencies certainly have some terror suspects who are Muslim, and some mosques that are suspected of ties to terrorism, under surveillance. Trump made a careless, egregious mistake by not paying attention and batting down the idea when it was first suggested to him by the press.