Why, on Sunday morning, did Donald Trump humiliate his secretary of state by tweeting that Rex Tillerson “is wasting his time trying to negotiate with Little Rocket Man”? In policy terms, it makes no sense. If Trump wants to break off diplomatic discussions with North Korean leader Kim Jong Un (which is in itself lunatic, but that’s a different column), why not inform Tillerson privately? Why destroy Tillerson’s already meager credibility and thus render him useless as a negotiator in the future?

The most plausible answer lies in the realm not of policy but of image. Trump, by his own admission, rarely reads. He knows little about domestic or international affairs. But he loves movies and according to one estimate, watches five hours of television a day. For 14 years, he starred in a reality TV show.

This helps explain why Trump so often describes political figures as if they’re characters on screen. According to The New York Times, he said Mike Pence looked like a vice president out of “central casting.” He reportedly used the same phrase to describe Mitt Romney as secretary of state. Top aides said he would never give the job to George W. Bush’s former UN Ambassador, John Bolton, because Bolton sports a moustache.

“Don’t forget,” Trump’s old friend Chris Ruddy told The Washington Post, “he’s a showbiz guy. He was at the pinnacle of showbiz, and he thinks about showbiz. He sees this as a business that relates to the public.”

For Trump, being president is less about enacting policies than staging scenes. And his favorite scene involves an inhuman villain, a feckless wimp, and an old-fashioned tough guy who saves the day. Characters one and two change depending on the subject. Character number three is always him.

Think about Trump’s discussions of immigration. There are the “bad hombres” or “rapists”: dehumanized villains. There are the politicians who are “weak” (one of Trump’s favorite words) on border security. And then there’s Trump, who will “make America safe again.”

Or consider Trump’s comments about torture. There are the terrorists, whom Trump frequently describes as “animals.” They’re not really human. Then there are the politicians, too timid to protect the country. At a rally during the GOP primaries last February, Trump cast Ted Cruz in that role. “So they are asking Ted Cruz, ‘What do you think of waterboarding?’” Trump told the crowd. Then he began playing Cruz for the audience: “‘Well, uh, um, uh, what do I say? I want to be politically correct. Waterboarding is so terrible.’” Then Trump switched back to his role. “Then they said to me, ‘What do you think of waterboarding?’ I said I think it’s great, but we don’t go far enough.”

At one level, Trump’s structure is familiar. For decades, some conservative politicians have described the world as comprising ruthless enemies (the Soviet Union, Saddam Hussein, violent criminals), appeasement-minded liberals who lack the clarity and guts to protect the nation, and John Wayne-style Republicans who restore safety and honor.

Trump’s innovation has been to apply the formula beyond the normal confines of public policy. He applies it, for instance, to the NFL. There are the unpatriotic players (the “son of a bitch” who “disrespects our flag”). There are the owners who are too weak to do anything about it. And there is Trump, who demands a return to patriotism and order.

But even when Trump does apply the formula to Washington politics, he does it in ways that flout preexisting norms. Traditionally, presidents don’t publicly insult their cabinet members. For Trump, however, that’s sometimes what the scene requires. Consider his discussion of the firing of James Comey. Comey is the villain (“a liar” and “a nut”). Trump is the hero who fires him. And the feckless softie who lets the villain run wild? Attorney General Jeff Sessions, whom Trump called “very weak” for recusing himself and thus not quashing the Russia investigation.

Now, Kim Jong Un is the villain (a “madman,” “Little Rocket Man”). Trump is the guy willing to use force, the guy threatening “fire, fury, and frankly power the likes of which this world has never seen before.” Then there are the wimps who won’t stand up to Pyongyang. In early September, Trump cast South Korea’s new president Moon Jae In in this role. (“Their talk of appeasement with North Korea will not work, they only understand one thing.”) He’s also cast the government of China. (“They do NOTHING for us with North Korea, just talk. We will no longer allow this to continue.”)

And Tillerson? He’s not the only administration official who has tried to counteract Trump’s Strangelovian tone. Defense Secretary James Mattis has, too. But Trump has already scripted Mattis: He’s “mad dog,” today’s General George Patton. He’s the wingman who proves Trump’s own toughness. So that leaves Tillerson to play the part of wimp.

It’s humiliating, to be sure. But also likely temporary. One day soon, Trump will assign the role to someone new.