In the weeks after President Emmanuel Macron called a snap election last summer that resulted in a deeply divided French Parliament, if his name came up it was often to call for his resignation.
The unpopular president, long derided by critics as aloof, all-controlling and arrogant, looked certain to ride out the final three years of his term as a lame duck atop an unstable government of his own creation, with a rotating cast of prime ministers, and little to show for it.
But President Trump has changed that. The American leader has abruptly reversed 80 years of friendly policy toward Europe, withdrawing support for Ukraine and siding with Russia, leaving European leaders panicked and lost. In doing so, he has made this Mr. Macron’s moment.
The French president, who once seemed on the verge of disappearing, is now in the headlines daily. Mr. Macron has gathered European leaders repeatedly in Paris, rushed to Washington and later to London, and generally become the focal point of Europe’s struggling effort to stand on its own feet.
After years of warning of the “imminent brain death” of NATO, Mr. Macron’s admonition now seem prescient as Mr. Trump threatens to turn his back on the alliance.
Mr. Macron’s talk of European boots on the ground to help keep the peace in Ukraine, rejected not long ago as impossible by incredulous allies, is now a plan being worked through as a plausible way to stem the fighting.
Similarly, Mr. Macron’s vision of a Europe with “strategic autonomy” from the United States was once largely dismissed as a distant idea from a man more prone to sweeping statements than follow through. The Russian invasion of Ukraine has since caused him to put more emphasis on a “European pillar” within NATO. But other European leaders seem ready to follow him toward the goal of allowing Europeans to better defend themselves.
“Crises are very good for a president. They put them back in the center,” said Vincent Martigny, a professor of political science at the University of Nice, Côte d’Azur.
In addition, he said, “Macron is the only one who can be the leader.”
German’s next likely chancellor, Friedrich Merz, has yet to form a government. Though the crisis has pushed Prime Minister Keir Starmer of Britain closer to the Europe Union, his country is no longer an E.U. member. And it is not clear that the efforts by Prime Minister Giorgia Meloni of Italy to mediate tensions with European allies particularly interest Mr. Trump.
So Mr. Macron has stepped into the leadership vacuum.
After Vice President JD Vance castigated European leaders during his speech at the Munich Security Conference last month, signaling the American president’s radical shift in foreign alliances, the French president and his office sprang into action.
Mr. Macron called a first meeting of European leaders in Paris almost immediately after the conference ended, followed by a second one the next day. He was the first European leader to go to Washington to speak directly to Mr. Trump, briefing his fellow European Union colleagues on the meeting afterward.
A few days after a disastrous visit to the White House by the Ukrainian president, Volodymyr Zelensky, both Mr. Macron and Mr. Starmer coached their ally on how to repair the situation.
According to a French diplomat close to Mr. Macron, the French president speaks to Mr. Trump every second day, on average, and to Mr. Zelensky and Mr. Starmer even more regularly.
The path forward for Europe now appears to follow much the course Mr. Macron has pointed to for years.
In recent days, his once distant-seeming plan for European troops to enforce any peace deal between Russia and Ukraine has begun to take more solid form. Britain and France have already committed troops, and, the Danish foreign minister, Lars Lokke Rasmussen, said on Monday that his country was also prepared to take part.
On Tuesday, Mr. Macron welcomed military leaders from some 30 countries who gathered in Paris for a defense and security conference, to solicit further commitments.
One of Mr. Macron’s boldest gestures has been to open discussions with European leaders about sharing the protection of France’s nuclear arsenal with them. Besides Russia, France and Britain are the only two countries in Europe with nuclear weapons.
The suggestion spoke to the leadership status Mr. Macron wants for France, a country that has long prided itself on the independence of its nuclear arsenal.
But it also reflects the new distrust of the American commitment to European allies, and Mr. Macron’s conviction that Russia’s aggression would expand farther if left unchecked without the promise of nuclear protection.
“We are entering a new era,” he said during a televised speech at the top of the French news last week. “Peace is no longer guaranteed on our continent.”
He added, “I want to believe the United States will remain by our side, but we must be ready if that doesn’t happen.”
Yet it remains far from certain whether any of Mr. Macron’s frantic action will prove successful. On Tuesday, Ukraine said it would be open to a cease-fire with Russia, but Moscow has given no indication that it is prepared to enter such a deal. Mr. Trump’s mercurial position seemingly changes by the day.
Mr. Macron’s presumption of European leadership has also at times irritated some allies. During a call to debrief his fellow European leaders about his trip to Washington, Ms. Meloni of Italy challenged Mr. Macron about in what capacity he had gone to the White House, according to people familiar with the call.
Italy’s defense minister, Guido Crosetto, accused Mr. Macron of offering European troops to Ukraine without having “the decency” to consult other E.U. countries.
“You don’t send troops like you send a fax,” Mr. Crosetto, whose government has opposed deploying troops to Ukraine, wrote on X, the social media platform.
Then there are all the practical issues, of how Mr. Macron will fund such a spending increase while France is facing a budgetary crisis.
He has prepared his country for the threat of war, announcing an increase of military spending over the next five years — with no additional taxes, he promised — and an expansion of weapons manufacturing. After the United States, France is the second biggest arms exporter in the world.
Other European countries, too, have announced that they will increase their military spending, potentially aided by proposals from the European Commission, including a €150 billion, about $164 billion, loan program to pay for more weapons and technology.
But the larger existential crisis has eclipsed all finnicky practicalities for the moment. In France, recent polls show the president’s approval rating is up from 4 to 7 points to the high 20s and low 30s — the biggest jump since the arrival of Covid in 2020, according to the monthly barometer by the French Institute of Public Opinion.
The French populace largely agree with him — that Europe must continue to support Ukraine and invest more in its own defense against a potential Russian threat, and that the United States can no longer been seen as a dependable ally.
Even many of the president’s political opponents have praised his diplomatic efforts and agreed with his analysis.
“I’m not a Macronist at all, but he was pretty good. The important thing is to try to unite people and convince them that the situation is pretty serious and that we obviously need a national mobilization,” said Cédric Perrin, a senator with France’s Republican Party who presides over the French Senate’s foreign affairs and armed forces committee.
Rather than the man meeting the moment, it seems the moment has arrived to what Macron has been saying since soon after he was first elected in 2017, when he delivered his first long speech at the Sorbonne extolling the urgent need for Europe to step from America’s shadow.
Back then, a Czech politician, Andrej Babis, who months later became the country’s prime minister, offered a back-handed slap: “He should really concentrate on France.”
Today, many in Europe concede Mr. Macron was right all along.
“In Czechia we strongly appreciate the leadership of the president of France,” said Czech Ambassador to France, Jaroslav Kurfürst. “Emmanuel Macron has earned a lot of credibility in our part of the world.”
Reporting was contributed by Emma Bubola in Rome, and Aurelien Breeden in Paris.