As human beings, you’d think we’d be better at understanding how our minds work. We are the most rational creatures in existence, capable of great mental feats, and we still struggle to grasp the emotional complexity that makes us who we are. We have an entire science dedicated to it now. Psychology hopes, through study and observation, to come up with some sort of biological or behavioral explanation for why we do what we do, and why we think the way we think. But still, males struggle to understand females, parents wrestle with their kids’ choices, and an entire nation fails to self-diagnose its woes.

The man who got closest to a suitable diagnosis is now sitting in the White House. He’s still perhaps one of the only politicians who understands his voter base, its psyche, and what it ails from: discontentment. But what Trump doesn’t understand is that discontentment doesn’t remain discontentment. Thanks to psychology, we know that base emotions can spiral in somewhat of a snowball effect if left unchallenged. Discontentment breeds anger, anger breeds rage, and on and on until something breaks and someone snaps.

Trump tapped into this frustration and channeled it into one of the most effective and unexpected candidacies the U.S. has ever seen. But that frustration hasn’t gone away. In fact, if it did, Trump would be in big trouble. He relies on it, expects it, encourages it.

We saw this last week during one of his rallies in North Carolina when the crowd started chanting “Send her back!” after Trump mentioned Rep. Ilhan Omar, a Somali-immigrant-turned-U.S.-citizen elected to Congress last year. Trump allowed the chant to continue for about 13 seconds, and later tried to distance himself from the crowd, saying he wasn’t “happy” about it. According to Stephen Miller, one of Trump’s senior advisers, it doesn’t matter what the crowd did as much as why they did it.

“The core issue is that all the people in that audience and millions of patriotic Americans all across this country are tired of being beat up, condescended to, looked down upon, talked down to by members of Congress on the Left in Washington, D.C., and their allies in many quarters of the media," Miller told Fox News’ Chris Wallace.

He’s right. It matters a great deal why a group of Americans thought it was acceptable, and even good, to demand an American citizen return to the country she immigrated from. Some have argued it was racially motivated. Or perhaps it was because Omar is a far-left politician they disagree with.

But again, I think Miller is, in part, right: Those Trump supporters wanted to send Omar back because she doesn’t want to “Make America Great Again.”

She’s part of the problem, in their eyes. She’s one of the radical leftists trying to hijack their nation and make it something that it’s not. And so, discontentment becomes anger.

There’s another reason the crowd broke out in that chant: It was at a Trump rally. This isn’t to say MAGA voters are racist or bigoted, but it is important. They wouldn’t chant “Send her back!” at a Ted Cruz rally, or a Marco Rubio rally, or even, fast forward several years, a Jim Jordan or Mark Meadows rally. Trump, with his populist policies and nativist rhetoric, has encouraged this kind of mindset. This nation is ours. We will put it first, and we won’t lose it to anyone — especially immigrants.

This is present at every Trump event. He says American companies are outsourcing jobs to cheap labor in different countries and the crowd screams “America First!” He claims illegal immigrants are bringing crime, drugs, and terrorism into the U.S. and the crowd cries, “Build the wall!”

The frustrating reality is that all of the problems Trump points out are very real. But instead of encouraging thoughtful discourse and practical solutions, he stokes division and anger through insulting tweets and partisan mudslinging. His supporters will say these things don’t matter: Finally, a president who does away with the establishment’s niceties! At last, a man in power who understands real Americans!

But they do matter, because discontentment doesn’t remain discontentment. History shows what a nation of rage can do.