Mary Calvert / Reuters

On Sunday, Iranian President Hassan Rouhani said in a televised speech to a domestic audience that the United States cannot prevent his country from exporting oil, adding that “peace with Iran would be the mother of all peace and war with Iran would be the mother of all wars.”

Donald Trump could have responded like an unflappable world leader. Instead, he replied in the favorite style of easily baited idiots: He posted an all-caps tweet. “To Iranian President Rouhani,” he wrote. “NEVER, EVER THREATEN THE UNITED STATES AGAIN OR YOU WILL SUFFER CONSEQUENCES THE LIKES OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE. WE ARE NO LONGER A COUNTRY THAT WILL STAND FOR YOUR DEMENTED WORDS OF VIOLENCE & DEATH. BE CAUTIOUS!”

By responding that way, Trump dramatically inflated the reach of Iranian words that would’ve otherwise been ignored. And he spoke as though rhetoric that wasn’t even particularly bellicose is itself good reason for war.

The episode reflects poorly on his fitness to be president. Maybe he is bluffing—that is to say, maybe he wouldn’t, in fact, launch a possibly catastrophic war over mere words, preferring to ground such a momentous decision in the actual substance of American national security. If so, he spoke recklessly: America gains exactly nothing from a bluff of that sort, and risks exposure if Iran chooses to call him on his words. Trump foolishly put the U.S. in a reactive position.

Then again, maybe the president was serious. That would be much worse. That would mean he is willing to launch a potentially catastrophic war over something as inconsequential as a foreign leader saying, in effect: You’d better not go to war with us, you’ll regret it if you do. Starting wars over such meager threats would all but abolish peace.

Trump has long indulged the habit of erratically shooting his mouth off in needlessly antagonistic ways. It used to be that his bellicose tweets were aimed at fellow celebrities such as Rosie O’Donnell. But his supporters made him president, so now, every time he tweets something needlessly bellicose in one of the many moments at which he seems to lack self-control, the odds of a geopolitical catastrophe increase a bit.

If Mike Pence were president, the threats to national security that come with having an erratic Twitter troll as president would be diminished. And I worry that Trump is the sort who’d start a war with Iran just to benefit himself politically—I fear that he was projecting here:

Why are so many Republicans still eager to risk their country’s future by backing Trump?

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