WASHINGTON — President Trump’s tenure as commander in chief came to a dramatic turning point on Thursday night as he found himself torn between his own competing advisers and his own competing instincts, teetering on the edge of the kind of military action he came to office vowing not to take.
In a volatile day of internal debates and an on-again, off-again strike against Iran, Mr. Trump confronted the essential conflict of his approach to national security. For two and a half years, he has veered between bellicose threats against America’s enemies and promises to get the United States out of the intractable wars of the Middle East. Now he had to choose.
Even as the military machinery cranked up to launch an attack on Iran on his orders in response to the shooting down of an unmanned American spy drone, Mr. Trump called it off, opting for restraint over retaliation, at least for now. The argument may not be over. Administration officials would not divulge many details of the discussion. But no one doubted this could be a defining juncture in Mr. Trump’s presidency.
This moment of truth was probably inevitable since the day in 2017 that Mr. Trump withdrew the United States from the international nuclear agreement with Iran negotiated by President Barack Obama and decided to unilaterally reimpose crippling sanctions. With its economy crumbling, Iran was always prone to lash out, forcing Mr. Trump to choose between war and peace.
“In some ways, President Trump is on a collision course with himself,” said Robert Malley, the president of the International Crisis Group and a former Iran adviser to Mr. Obama. “He says he’s in favor of maximum pressure and he’s against military confrontation when it comes to Iran but both of those things can’t be true because one of those things can lead to the other.”
Even if Mr. Trump ultimately does not resort to force in response to the drone attack, the decision on how far he is willing to go in terms of Iran may not be far-off. The episode was only the latest in a series of relatively modest provocations, but Tehran has said it is about to turn its nuclear program back on in a way that will go beyond the limits of the agreement Mr. Trump abandoned.
“The Iranians are going to continue to test his mettle and we will soon be at the come-to-Mohammed moment,” said Reuel Marc Gerecht, a former C.I.A. specialist on Iran at the Foundation for Defense of Democracies, who believes a military response at some point may be necessary.
“You’re going to learn more about Mr. Trump,” he added. “You’re also going to learn more about the American people. You’re going to see where everybody is at on this. Do we still want to play power politics in the Middle East? The answer may be no, we don’t. But I think judgment time is coming fairly quickly.”
Mr. Trump has always been a commander in chief of contradictions. He has adopted a modified version of Theodore Roosevelt’s maxim when it comes to overseas military threats — speak loudly and carry a small stick. Or carry a big stick but wave it around without actually using it much.
He talks like a bellicose warmonger but acts like an isolationist peacenik. He warns enemies that he will rain down “fire and fury” on them while striving to avoid more of the foreign wars he blames his predecessors for waging.
Mr. Trump seemed to calculate that tough words and a better-funded military serve as a deterrent that keeps potential rivals from daring to take on the United States. But critics argue that tough words themselves can be dangerous and, even if inadvertently, can escalate into a shooting war.
While Mr. Trump credits his apocalyptic threats to “totally destroy” North Korea with pressuring its leader, Kim Jong-un, to the negotiating table, the situation in the Middle East presents different dynamics. In Asia, North Korea’s neighbors in China, Japan, Russia and South Korea were not at all eager for a military clash. But in the Middle East, Iran’s adversaries like Israel, Saudi Arabia and the United Arab Emirates take a more aggressive stance.
Likewise, Mr. Trump is surrounded within his own team by hawks like Secretary of State Mike Pompeo and John R. Bolton, the national security adviser, who favor a strong response to Iran, even as the president resists. The contrast in their perceived positions has created a deep confusion at home and in the region about the administration’s policy.
“It’s a house divided,” said Rahm Emanuel, a former congressman who served as the White House chief of staff under Mr. Obama and later as mayor of Chicago. “You have Bolton and Pompeo on one side and Trump and the Joint Chiefs on the other. And now we have a problem because we have no strategic coherence.”
Mr. Trump’s allies, however, said his resistance to foreign quagmires would not stop him from using force if necessary. “This is a president who was elected to get us out of wars and not get us into new wars,” said Fred Fleitz, a former chief of staff to Mr. Bolton at the White House and now the president of the Center for Security Policy. “But unlike Barack Obama, the use of force is on the table and he will use it if he needs to.”
Mr. Trump in recent days has minimized the possibility of military conflict with Iran. After explosions on two oil tankers were blamed on Iran, he played down the incident, telling Time magazine that “so far, it’s been very minor” and intimating he would not go to war over something like that.
On Wednesday night, hours before the drone was shot down, the president told Sean Hannity on Fox News that he was not concerned by overseas challenges. “Everything is under control,” he said. “Don’t worry about a thing.”
His initial public reaction to the drone episode on Thursday appeared to indicate he would avoid action as he emphasized that no American lives were endangered and suggested it might have been an unauthorized move by someone who “made a big mistake.”
Indeed, his seeming reluctance to use force won praise from allies who oppose further overseas entanglements. “The very people — in some cases, literally the same people who lured us into the Iraq quagmire 16 years ago — are demanding a new war — this one with Iran,” Tucker Carlson, who has privately advised Mr. Trump, said on Thursday night on his Fox News show. “The president to his great credit appears to be skeptical of this. Very skeptical.”
Mr. Trump has not shied away from the use of force at times. He has twice ordered cruise missile strikes on Syria to retaliate for chemical weapons attacks on civilians and he has authorized troop deployments to various countries to hunt down terrorists. He continued the battle against the Islamic State that he inherited from Mr. Obama and gave commanders on the ground more leeway as they successfully recaptured territory in Iraq and Syria.
But Mr. Trump has sought to bring home troops from the Middle East even at the cost of losing his original defense secretary, Jim Mattis, who resigned in protest after the president abruptly ordered a force withdrawal from Syria last winter without first consulting allies. He has consistently expressed scorn for the wars in Afghanistan and Iraq waged by Mr. Obama and President George W. Bush.
“We’re charting a path to stability and peace in the Middle East, because great nations do not want to fight endless wars,” he said this week in his re-election kickoff speech in Orlando, Fla. “They’ve been going on forever. Starting to remove a lot of troops. We’re finally putting America first.”
At the same time, he has agreed to speed up deployment of an aircraft carrier to the region and send another 1,000 troops in the face of Iranian threats.
“For a president who says he wants to wind down military commitments in the region, scrambling aircraft carriers and deploying thousands of new troops is not the sign of a policy that is working,” said Brett McGurk, the president’s former envoy for countering the Islamic State who, like Mr. Mattis, resigned last year in protest of the Syria decision.
“And because there is no national security process that connects to Trump,” Mr. McGurk added, “he does not seem to have realized that his national security team, month after month, was boxing him in to a point at which he would be forced to back down or resort to military force.”
But Mr. Fleitz, the former Trump aide, said Iran was making a strategic mistake if it believed the president’s oft-expressed desire to get out of foreign wars means he will not use the military eventually.
“I don’t think they think the president will respond with force,” he said. “But I think they’ve miscalculated. His patience is not endless.”