Whether or not the president thinks about it strategically or (more likely) just acts on instinct, his words invariably follow a polarizing script. First he identifies a point of civic tension — in this case, Kaepernick’s protest. A portion of the country feels anger at the gesture of dissent from the national anthem — some of them because of outright racism, but others because they see it as a sign of disrespect toward the country at a moment that’s set aside for patriotism. Then there’s a second group — probably millions strong — that doesn’t exactly admire the protest, but also doesn’t especially care much one way or another. Let’s call them the tepid.

By expressing, intensifying, and amplifying the views of the first group with all the volume of the presidency, Trump emboldens those who were already angry. Now they have a champion in the White House. At the same time, he provokes the left into issuing a flood of angry counter-denunciations that reduce everyone ill-at-ease with the original protest (including our ambivalent tepids) to the category of racists and white supremacists. Meanwhile, the presidential attacks inspire additional athletes to engage, out of solidarity, in more of the same type of protest. Now far more players kneel during the anthem or refuse to come on the field to salute the flag — and a wide range of news and sports commentators explicitly take their side.