But the new polling is alarming enough for the Left that the progressive group Priorities USA released a memo suggesting a readjustment. It posits that Democrats were winning the tax and health-care debates, then “in the last few weeks, Democrats turned their attention to other issues.”

What other issues? Well, every other issue. Immigration, of course. But, otherwise, the crisis du jour — “s***hole countries,” etc. — and the hardy perennials of Russia and obstruction, sometimes switched around to obstruction and Russia for novelty’s sake.

Trump is the racetrack rabbit that keeps Democrats running in a perpetual cycle of outrage. This doesn’t mean the president is playing three-dimensional chess, or that the unending Twitter-fed controversies help him. Surely, if he arranged for a 60-ton M1 Abrams tank to ceremonially crush his phone at his hoped-for military parade down Pennsylvania Avenue, his approval rating would bump up a couple of points.