San Francisco 49ers safety Eric Reid (35) and quarterback Colin Kaepernick (7) kneel during the national anthem before an NFL football game against the Los Angeles Rams in Santa Clara, California, Sept. 12, 2016. NFL owners have approved a new policy aimed at addressing the firestorm over national anthem protests, permitting players to stay in the locker room during the "The Star-Spangled Banner" but requiring them to stand if they come to the field. The decision was announced Wednesday by NFL Commissioner Roger Goodell during the league's spring meeting in Atlanta. Credit: Marcio Jose Sanchez | AP

It’s impossible to predict what the Donald Trump era will look like in one or two decades. But eventually, against a backdrop of some version of normal, historians will do what they’ve always done: Try to explain what happened.

By that time, they will know what, if anything, the Mueller investigation uncovered, which may help explain how Trump became president. They will study the discontentment of non-college whites, who embraced a presidential candidate with no obvious qualifications beyond his eagerness to “shake things up” and “drain the swamp.” They will thoroughly analyze the Trump phenomenon in light of a confusing combination of economic dislocation, social media, tribalism and incivility.

But few episodes provide as much insight into the Trump era — into both how he became president and how he governs — than a minor event that occurred last week: The National Football League adopted a policy that mandates that all players on the field must stand for the national anthem or else be fined by the league.

The story begins in 2016 with Colin Kaepernick, the then-quarterback for the San Francisco 49ers, who declined to stand for the national anthem. Instead, he took a knee in order to direct attention toward the racial injustices that he believes persist in the United States.

Others joined him in protest and considerable controversy ensued. The NFL, the owners and the players union looked for ways to accommodate every American’s right to free speech with the desire to give the fans a product unsullied by politics. They were unsuccessful. Eventually Kaepernick lost his job; in the minds of many who know more about football than I do, he is a more talented quarterback than some who are currently playing in the NFL.

Kaepernick’s banishment is simply wrong. But the league and the owners might not have gone so far wrong if Trump hadn’t gotten involved. During a speech in Alabama last September, Trump said, “Wouldn’t you love to see one of these NFL owners, when somebody disrespects our flag, to say, ‘Get that son of a bitch off the field right now. Out! He’s fired. He’s fired!’”

Predictably, his audience loved it.

And last week the NFL and the owners also gave Trump what he wanted, earning his praise. In fact, he went a step further, saying of players who choose to stay in the locker room during the anthem, “Maybe you shouldn’t be in the country.”

Trump didn’t invent this sort of intolerance, but he understands instinctively how to exploit a sentiment that resides just beneath the surface in America. The sort of super-patriotism that cannot tolerate dissent, however, is the opposite of the American ideal and is incompatible with the First Amendment.

Trump understands also the power and appeal of grievance, the feeling that other people are taking advantage of us. Americans love football, but many harbor resentments over players’ astronomical salaries for playing a game that many Americans cannot afford to attend.

And for many, the fact that most of the players are black intensifies the grievance. Trump understands this and knows instinctively how to capitalize on it.

Finally, Trump sees people, whether wives, Cabinet members or immigrants, as commodities, and no American professionals are more commodified than football players. The ones at the top are richly rewarded, but their fame and fortune come at an enormous physical and mental toll. The rest are bought and sold and lavishly courted until they’re no longer useful and then they’re discarded.

So future historians could do worse than to try to explain the Trump era in terms of the restrictions put last week on football players’ freedom to speak. The restrictions embody some of the worst that Trump has brought out in us: intolerance, coerced patriotism, tribalism and a hint of racism and name-calling. They embody a narrow-minded contempt for people who see things differently than we do.

And most important, historians will note the most striking phenomenon of all — and this is Trump’s true genius: Somehow he induced many of the rest of us to simply go along with him.

John M. Crisp is a Tribune News Service columnist.

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