It really wasn’t all that bad.

That, at least, was the consensus response from a dozen historians to whom Politico posed a question in the waning hours of the old year: “Was 2017 the Craziest Year in U.S. Political History?”

Only one answered in the affirmative. The rest deferred to years they consider crazier, including 1861, when America went to war with itself over slavery; 1919, the year of the “Red Summer” race riots; and 1968, the year of the Democratic convention riots, the Tet offensive and the assassinations of Martin Luther King Jr. and Robert F. Kennedy. One historian, H.W. Brands of the University of Texas, said that, compared with the first years of the Lincoln, Franklin Roosevelt and George H.W. Bush and George W. Bush presidencies, our first year under Donald Trump was “a yawner.”

I beg to differ.

Granted, the question they were asked was so vague – how are we defining “crazy,” after all? – as to be in some sense unanswerable. And it’s true enough that 2017 saw no major transformative or disruptive events on the scale of 1861 or even 1968.

Still, I’d argue that in essentially writing it off as a so-called “yawner,” the panel underestimates 2017. Something did happen last year. It was easy to miss because it was not stark or spectacular – no riot, war or secession. No, this was subtle and insidious, but all the more foreboding for that.

It was, you see, the year that the last norms fell. Those norms, i.e., our sense of what is allowable and acceptable on the public stage, have been eroding for years, but 2017 saw the process accelerate like Usain Bolt. It was the year things that are not supposed to happen occurred all day, every day.

A president just doesn’t ridicule his own FBI and CIA. Or interfere with independent investigations. Or bully the free press. Or speak kindly of white supremacists and credibly accused child molesters. Or use his office for personal gain when everyone can see him doing it or lie when even babies know he’s lying. He doesn’t threaten nuclear war via Twitter.

A president simply doesn’t do those things. Except that now, evidently, he does. And that’s scary.

Politics – and civil society as a whole – rests on a foundation of largely unspoken agreements, a social covenant that defines us in relation to one another, sets forth the duties we owe and the expectations we maintain in deference to the larger us. There have always been things our leaders did – and refrained from doing – not necessarily because the doing or not doing violated the law, but because it violated tradition, propriety, common sense, ethics, statesmanship, the dignity of high office and some native sense of right and wrong.

All of which were conspicuously absent from the presidency last year. The result has been anger, coarseness, political destabilization and a trickle-down nastiness visible both in anecdotes and in hate crime statistics. Nor is the source any mystery. As white fans jeered at players from a black and Latino high school during a basketball game: “Trump! Trump! Trump!”

Yes, 1919 brought riots, 2001, unspeakable terror. But 2017 was a sustained assault on the ideal of the larger us. It taught us how fragile is the social covenant, how susceptible to anyone willing to kick over the table, break the silverware and beat his chest. It taught us how shamefully docile some of us will be in falling in line behind such an individual.

Thankfully, it also taught us that civil society is not something you take for granted. It’s a choice you make, a thing you have to fight for.

Which will be a fitting mission for 2018 and beyond.

Leonard Pitts Jr., winner of the 2004 Pulitzer Prize for commentary, is a columnist for The Miami Herald. He can be contacted at:

lpitts@miamiherald.com