The president has been understandably confident in his supporters. They appreciate his efforts, admire his accomplishments (Justice Neil Gorsuch, ISIS’ setbacks), claim bragging rights for possibly related occurrences (the stock market’s rise), and feel sympathy for him as an outsider up against the swamp. They see his roughness as evidence of his authenticity, so he doesn’t freak them out every day. In this they are like Sarah Palin’s supporters, who saw her lack of intellectual polish as proof of sincerity. At her height, in 2008, she had almost the entire Republican Party behind her, and was pushed forward most forcefully by those who went on to lead Never Trump. But in time she lost her place through antic statements, intellectual thinness and general strangeness.

The same may well happen—or be happening—with Donald Trump.

One reason is that there is no hard constituency in America for political incompetence, and that is what he continues to demonstrate.

The first sign of political competence is knowing where you stand with the people. Gallup this week had him at 36 percent approval, 59 percent disapproval. Rasmussen has him at 41 percent, with 57 percent disapproving. There have been mild ups and downs, but the general picture has been more or less static. Stuart Rothenberg notes that at this point in his presidency Barack Obama had the approval of 48 percent of independents. Mr. Trump has 33 percent.

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