Standing in the rotunda, Prime Minister Giorgia Meloni of Italy was a privileged guest at President Trump’s inauguration.
The only European leader to attend the event last month, Ms. Meloni shares many of Mr. Trump’s conservative, nationalist impulses. She is friendly with his billionaire adviser Elon Musk. Many of her supporters hope that the Italian leader’s special relationship with Mr. Trump will bolster Italy’s standing — and her own.
But even as Ms. Meloni joined a standing ovation for the new American president, it took only moments for Mr. Trump to remind her and others on Europe’s right that the unpredictable American president may be as much an adversary as an ally.
“I will, very simply, put America first,” Mr. Trump said in his inaugural address. “We will tariff and tax foreign countries to enrich our citizens.”
Since then, Mr. Trump has warned that he will “definitely” slap Europe with tariffs “pretty soon,” raising the same wariness that many Europeans feel among those on the right who would seem to be his natural allies.
While Mr. Trump promises to answer to no one as he prioritizes American interests, many nationalist parties in Europe pledge to do the same for their own countries. Mr. Trump’s threats go to the heart of their own agendas, and they could hurt the core constituencies on which nationalist parties have expanded their appeal.
Potential tensions around trade highlight some of the fundamental contradictions that could emerge from an international alliance of nationalists, with questions on whether their friendship can withstand a collision of competing interests. Leaders are also worried about a possible American disengagement from Europe’s security, and Mr. Trump’s threats to allies who do not meet military spending targets.
“To support a guy who might have negative effects on your country, that’s not a good strategy,” said Renaud Labaye, the general secretary of the far-right National Rally in France’s National Assembly.
Jordan Bardella, the president of the National Rally, said last month that he respected Mr. Trump and was inspired by how quickly he was filling planes with Colombian deportees and threatening the country with tariffs if they didn’t let them land.
But he also painted Mr. Trump as an existential threat to France and Europe. Any tariffs that Mr. Trump might put on French agriculture would hurt French farmers — whose support Mr. Bardella cannot afford to jeopardize.
“If we don’t defend our interests, we will disappear,” he said at a news conference last week.
That coolness differed from the National Rally’s reaction to Mr. Trump’s last election in 2017, when Marine Le Pen, the party’s former president, praised him effusively, and went to Trump Tower in New York hoping — unsuccessfully — to bump into him on the eve of his inauguration.
Mr. Labaye said that it was very useful for the National Rally to have Mr. Trump raise the anti-immigration agenda to a global level in 2017. Now, with nationalist parties surging in Europe, they no longer need President Trump’s services as much.
President Trump’s style could put off many French voters, Mr. Labaye added. “It’s not our culture — being over the top, trash-talking, speaking loud,” he said.
If anything, too much of an association with Mr. Trump could threaten the National Rally’s long and increasingly successful strategy to “undemonize” the party’s image and broaden its appeal among French voters.
“There is a radical aspect of Trumpism today,” said Maya Kandel, a researcher who studies the right in the United States and its links to Europe at the Sorbonne University in Paris. “They don’t know if they want to be part of it or if they want to stick with their normalization plan.”
Still, for as much as Mr. Trump has generated nervousness among his allies, his victory has also galvanized Europe’s right-wing parties, adding momentum to the conservative project they promote.
Some, like the Alternative for Germany, have openly embraced endorsements from Mr. Trump’s right-hand man, Mr. Musk, hoping to gain new stature and legitimacy.
The party, parts of which have been classified as extremist by German intelligence agencies, has seen only a modest bump in the polls following Mr. Musk’s endorsement, and it might not be related to his efforts. Recent polling shows that three-quarters of Germans see Mr. Musk’s attempts to influence German elections as “unacceptable.”
The same poll found that 71 percent of respondents in Germany and Britain, where Mr. Musk has also meddled in the political debate, hold a negative view of him.
For the moment, Mr. Trump’s biggest influence may be in the imitation of his tactics, as demonstrated by a gathering of far-right parties in Madrid this weekend under the banner, “Make Europe Great Again.”
The attendees are expected to include Prime Minister Viktor Orban of Hungary; France’s Ms. Le Pen; and Matteo Salvini, whose League party is part of Ms. Meloni’s governing coalition. They are certain to gush over Mr. Trump’s new presidency.
But beneath the confident veneer lurks the gnawing uncertainty over what Mr. Trump actually means for Europe.
Ms. Meloni’s allies hope she can mediate between the United States and Europe in trade negotiations. “We want to be a bridge,” Italy’s foreign minister, Antonio Tajani, told the newspaper Corriere della Sera on Monday.
Experts caution that if she tried to play the role of Trump-whisperer Ms. Meloni could also find herself squeezed between a notoriously capricious American president and the European Union, in case the relationship turns more adversarial than it already is.
In case of conflict, it would be hard for Ms. Meloni to side with Mr. Trump, said Jean-Pierre Darnis, a professor at Côte d’Azur University in Nice focusing on Italian foreign relations.
Italy is a founding member of the European Union, and it depends on the E.U. as its largest trading partner and for billions in post-pandemic recovery funds.
“It’s E.U. first,” said Mr. Darnis. “Then you deal with the U.S.”
Beniamino Irdi, a senior fellow with the Atlantic Council’s Transatlantic Security Initiative, said that no matter how much Ms. Meloni and Mr. Trump got along, political affinity could hardly sustain a relationship with someone like Mr. Trump, who has generally embraced a transactional approach to foreign relations.
Their relationship “can give Meloni some meter of advantage on the starting line,” Mr. Irdi said, “but it’s not enough.”
That may be especially true if Italy’s own interests are on the line.
According to a study by Prometeia, an Italian consulting firm, a 10 percent increase in American tariffs on Italian products would cost Italy from 4 to 7 billion euros.
Mr. Trump has threatened to retaliate against European countries who do not meet NATO’s spending commitments for their militaries. At 1.5 percent of its output spent on defense, Italy is far below the unofficial commitment of 2 percent — and even further below the 5 percent Mr. Trump now demands.
Ms. Meloni’s closeness to Mr. Musk has also exposed her to criticism by opponents who were quick to point out that the Italian leader has in the past railed against foreign actors meddling in other countries’ domestic politics.
Italy has also long been in talks with Mr. Musk’s SpaceX for a potential deal to provide secure communications for government and military officials through Starlink.
But when news about the Starlink talks emerged, the opposition accused Ms. Meloni of cozying up with Mr. Musk at the expense of a satellite initiative that the European Union was also building.
Ms. Meloni defended herself by saying that she was only exploring the possibility and that, for now, there was no alternative to Mr. Musk’s satellites.
At the same news conference, she also found herself facing multiple questions about her relationship with Mr. Musk and his interfering in the politics of other countries.
So far, Ms. Meloni has defended her allies.
“George Soros,” she said, referring to the billionaire American investor and longtime Democratic donor whose support of liberal causes has made him a boogeyman of the right. “That’s what I consider dangerous interference.”
Jim Tankersley contributed reporting from Berlin.
