Mr. Le Drian said that the French president, Emmanuel Macron, planned to speak to his Iranian counterpart, Hassan Rouhani, by telephone on Wednesday about “our wish to stay in the agreement,” potentially widening a breach with the Trump administration.
But the real question for the Europeans, Mr. Shapiro said, “is not if they stick with the deal but will they stand up to the American effort to unravel it and take active measures to protect their companies and banks trading in Iran?” That would be “an extremely confrontational stance,” he said, “and it’s not clear that their companies really want that.”
While some think that they should double down on what has now become a pattern — keep talking to Mr. Trump and his aides, hoping to convince them of the need for trans-Atlantic solidarity — others have had enough.
There are increasing voices for rupture. In Britain, Emily Thornberry, the Labour Party spokeswoman on foreign affairs, said on Tuesday that it was time for Europeans to stop “this long and unnecessary indulgence of Donald Trump.”
A senior adviser to the European Union, Nathalie Tocci, said that the Iran deal was a lost cause, because “Trump and Europe have fundamentally different objectives.”
She said that Mr. Trump “is not interested in keeping a nuclear nonproliferation agreement but in regime change in Iran — it’s as simple as that.”
“We have to stop being wimps,” she added.
On climate and trade, on international law, and on the importance of multilateral institutions like the United Nations and the World Trade Organization, the rift with the Trump administration is real, said Ms. Tocci, director of the Italian Institute of International Relations and a close adviser to the European Union foreign policy chief, Federica Mogherini.