One of the important lessons Americans learned from Donald Trump’s election in 2016—and one still difficult for some of us to process almost four years later—is just how many of our fellow citizens are predisposed to authoritarianism.

In high school civics we were taught that “American authoritarianism” was an oxymoron. Authoritarianism was a relic of the past. America was a country founded on freedom, steeped in equality and justice, and uniquely immune to it.

We now know that this story is a national fairy tale. As I wrote in Politico nearly a year before Trump’s victory in 2016, the single factor that predicted whether a Republican primary voter supported Trump over his rivals was an inclination to authoritarianism. I published that article based on a national survey taken nearly a year before the presidential election, and it was followed by stories and reports elsewhere on how Trump was stirring up a deep, if often dormant, authoritarian strain in our politics.

In November 2016, voters had a chance to repudiate that strain. Instead, Trump was elected president. And […]