Given this history, there’s nothing surprising about Trump disseminating the works of Jayda Fransen. The interesting question is why he did it now. The simplest answer is that fear and hatred of Muslims boosts Trump politically. As Nate Silver has noted, Trump was losing ground to Ben Carson in the two months before November 2015, when the attacks in San Bernardino and Paris boosted fears of terrorism to levels unseen since the aftermath of 9/11. Trump responded to those attacks with a flurry of Islamophobia: musing about closing mosques and creating databases of American Muslims, insisting that New Jersey Muslims cheered 9/11, and proposing a Muslim ban, which was popular among Republican primary voters. By mid-December, Silver observed, Trump’s support in 538.com’s “high-sensitivity polling average” had risen eight points. Neither Carson nor any other GOP contender seriously threatened his lead in the national polls again.

Now Trump’s approval rating is stuck below 40 percent. ISIS is losing ground in Iraq and Syria, and thus receding somewhat as a focus of Washington debate. Fewer Americans cite terrorism and immigration—which for Trump supporters are inextricably linked—as their top concern compared with earlier periods this year. So it makes political sense for Trump to take a few minutes in the early morning to stoke rage against the people who during the campaign he repeatedly called “animals.” His decision to retweet Fransen’s videos wasn’t a gaffe. It’s a core part of his strategy for remaining president. And the weaker he grows politically, the more extreme his incitements to anti-Muslim violence will become.