Amanda Ripley is a contributing writer at the Atlantic.

As the war of both arms and words between Washington and Tehran continues, it’s a good time to consider humiliation, the emotion that more than any other drives the conflict between the United States and Iran. It is more important than battle plans or geopolitical strategy. It shapes the words and actions of President Trump and his Iranian counterparts. Earlier this month, we were all at its mercy, and we will soon be again.

It is curious that we hear so little about humiliation, because people who study conflict talk about it all the time. They liken it to the “nuclear bomb of the emotions,” as psychologist Evelin Lindner has written. And almost everywhere you find violence, you find humiliation in play.

Let’s start with the president. Trump has felt humiliated by Iran for years, as he keeps telling us. “They humiliated our country,” he said on Rush Limbaugh’s show three days after a U.S. drone strike killed Iranian Maj. Gen. Qasem Soleimani. On that show, Trump used the word “humiliated” four times.

On Limbaugh’s show, Trump referenced the Iranian seizure of two U.S. Navy river boats four years ago. After the boats veered into Iranian waters, the 10 American sailors were held for 15 hours before being released unharmed. But the Iranian military also released a photograph of the sailors on their knees, being detained at gunpoint. This subjugation provoked a strong reaction in Trump. “Iran humiliated the United States with the capture of our 10 sailors. Horrible pictures & images. We are weak,” he tweeted at the time. “I will NOT forget!”

And he has not forgotten. For Trump, that image was searing. Notice he did not say, "We look weak.” He said, "We are weak,” which is much more provocative. “So vividly I remember that day,” he said three months afterward.

On this point, I believe him. We all need to matter. It’s a fundamental requirement for life. When members of our group get insulted, degraded or killed, it can feel as though we don’t matter, either. Humiliation puts conflict on steroids.

Starting in the late 1960s, prison psychiatrist James Gilligan spent decades interviewing men who had been convicted of serious crimes. Again and again, he found humiliation hiding somewhere in their stories. “I have yet to see a serious act of violence that was not provoked by the experience of feeling shamed and humiliated, disrespected and ridiculed, and that did not represent the attempt to prevent or undo this ‘loss of face.’”

But not everyone who experiences disrespect interprets it the same way. Humiliation is subjective. So why did Trump experience this image of detained sailors as so intensely humiliating? Why didn’t it feel, for example, unjust or immoral? Why is humiliation such a common narrative for Trump? (In an informal Nexis search of news transcripts involving Trump, going back four years, the word comes up more than six times as often as it does in transcripts involving President Barack Obama over the same time period in his tenure.)

Whatever the cause, Iran's leaders seem to have noticed how easily Trump can be triggered.

Trump “deserves to be humiliated,” hard-line cleric Ahmad Khatami said in his Friday prayer sermon broadcast live by Radio Tehran in June. Six months earlier, Khatami said Trump’s decision to visit Iraq without prior announcement, due to security concerns, was “a confession to weakness and humiliation.” Intentionally or not, Khatami pushes Trump’s humiliation button again and again. In 2016, the Iranian military even reenacted the capture of the American sailors in a parade to celebrate the anniversary of the Iranian Revolution.

After greenlighting the killing of Soleimani, Trump himself revived old humiliations to gin up public support (just as Iranian leaders often do). Trump warned via tweet that the U.S. military had identified 52 targets to strike in Iran, in the event that Iran tried to take revenge. Why 52? That’s the number of U.S. hostages taken by Iran 40 years ago. Another humiliation. Back and forth it goes. Delivering Friday prayers this past week for the first time in eight years, the Ayatollah Ali Khamenei, Iran’s supreme leader, called Trump a “clown.”

There are people in the world who deliberately exploit conflict. They are conflict entrepreneurs, and, like Trump and Khatami, they too quickly frame events as “humiliating.” They detonate the nuclear bomb of emotion — sometimes for effect, sometimes to a specific end, sometimes both.

After the fall of communism and the bloody suppression of protests in Tiananmen Square, the Chinese government needed to regain public support. So the government launched a massive education campaign designed to highlight China’s collective humiliation by Japanese and Western imperialists, going back to the 1800s. The government recommended patriotic films, books and songs, including one book titled “Never Forget Our National humiliation.”

When it becomes our patriotic duty never to forget our humiliations, we are in a bad cycle. It is important to ask ourselves: Are our interests genuinely at stake? Is what we are experiencing really humiliating, or just unsettling or unfair? Conflicts can be plenty real enough without letting our emotions trigger mutually assured destruction.

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