Trump made little effort during the campaign to conceal the contradictions inherent to his isolationist posture and his crowd-pleasing saber-rattling. “We’re fighting a very politically correct war,” he said in one interview. “We’re not taking it to [ISIS], and we have to take it to them,” he said in another. During a NBC News forum last September, Trump said, “I think under the leadership of Barack Obama and Hillary Clinton, the generals have been reduced to rubble. They have been reduced to a point where it's embarrassing to our country. ... And I can just see the great, as an example, Gen. George Patton spinning in his grave as ISIS, we can't beat."

To right the ship, Trump repeatedly declared on the campaign trail—in his trademark bellicose style—that he would be much tougher on foreign enemies and adversaries than past presidents have been. He gleefully pledged to “bomb the shit out of” ISIS-controlled oil wells and then make off with the oil. He flaunted his support for the use of torture, and ridiculed anyone who opposed it. On multiple occasions, he said he would deter and demoralize terrorists by killing their families. If Trump was anti-war, he seemed decidedly pro-war-crimes.

In one particularly vivid example, Trump told a story (which turned out to be apocryphal) about former U.S. Army General John Pershing summarily executing Muslim prisoners with bullets soaked in pig’s blood. “He had his men load his rifles and he lined up the fifty people, and they shot 49 of those people,” Trump told a crowd in South Carolina. “And the fiftieth person he said ‘You go back to your people and you tell them what happened.’” For Trump, the moral of the story was in the kicker: “And for 25 years there wasn’t a problem, okay?”

Beyond fighting terrorism, Trump has often said the U.S. needs to be more “unpredictable” on the world stage. While running for president, he pointedly refused to take the potential use of nuclear weapons off the table, even in places like Europe. That probably wasn’t because he had big plans to bomb Estonia; it was because he wanted to place as few constraints on himself as possible, believing that the more nervous he made the world as commander-in-chief, the less likely it was that adversaries would mess with America. Some have identified this approach as a return to the “Madman Theory,” Richard Nixon’s belief that if his enemies thought he was unbalanced, he would have a stronger negotiating position against China on the Vietnam War.

But, of course, Trump does not have Nixon’s discipline or depth of knowledge, nor does he have George W. Bush’s level of conviction, or Barack Obama’s cerebral patience—all qualities that could have come in handy for a president who hoped to defy the vast Washington establishment in pursuit of a radical departure from foreign policy orthodoxy. Instead, Trump entered the Oval Office with a bone-deep belief in vengeance, a tendency toward impulsiveness, and a history of saber-rattling rhetoric.

There are strong arguments for and against Trump’s decision to intervene in Syria. But whether it happened this week or next, in Syria or someplace else, the president was bound to disappoint his isolationist supporters sooner or later.

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