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When President Trump abruptly announced plans to withdraw troops from northeastern Syria earlier this month, at least one European leader and key U.S. ally found out in a very public way: on Twitter.

“I thought that the United States and Turkey were in NATO, and then I discovered by tweet that the U.S. had decided to withdraw its troops and pave the way [for Turkey to launch its offensive] in the area,” French President Emmanuel Macron told reporters in Brussels last week. “Like everyone else, I realized that another NATO power had decided to attack partners of the coalition fighting [the] Islamic State.”

Trump had frightened European allies with his threats to withdraw from Syria before, announcing last winter that the Islamic State had been defeated and that U.S. troops would soon leave. That time, his own team was also deeply rattled. Multiple high-ranking officials, including then-Defense Secretary Jim Mattis, resigned shortly after his announcement. Trump later backtracked, saying U.S. troops would stay until they could ensure the Kurdish forces who led the fight against the Islamic State were safe and that the terrorist group was completely gone.

But the uproar last winter was something of a warning sign for Europeans, who were aware that between Trump’s stated desire to bring U.S. troops home and his habit of making snap decisions, the status quo in northeastern Syria remained tenuous. Still, when the White House suddenly abandoned years of U.S. policy this month, European allies were left racing to figure out what to do next.

“From a force protection standpoint and political standpoint, all European efforts in the northeast hinged on American commitment,” said Tobias Schneider, a Berlin-based research fellow at the Global Public Policy Institute. “Suddenly at once, without having any influence in the entire decision, Europeans were left out in the cold.”

In the weeks since, the fact that key European leaders do not have much of a backup plan has been put on full display.

Macron has described the withdrawal and NATO’s lack of response as “a serious mistake by the West and NATO in the region.” In Britain, Prime Minister Boris Johnson has been somewhat preoccupied with his desperate efforts to push through the latest version of a Brexit plan. This week, German Defense Minister Annegret Kramp-Karrenbauer controversially suggested that Berlin establish a security zone in northeast Syria.

On Thursday, NATO Secretary General Jens Stoltenberg said he saw it as a positive sign that members of the alliance are coming forward with suggestions, although he acknowledged “there are many challenges and many questions that have to be answered.”

Defense ministers belonging to the NATO alliance gathered in Brussels on Thursday, and ahead of the meeting, diplomats asked about Germany’s plan and said they looked forward to learning more about it from Kramp-Karrenbauer. But several noted that it has yet to earn real backing even from inside Germany.

Schneider called Kramp-Karrenbauer’s proposal “completely unmoored from reality” and said she probably publicized such a suggestion to gain attention at home, where she is considered a likely successor for German Chancellor Angela Merkel, who plans to step down in 2021, at the end of her term. But no matter what types of military proposals are now made, Schneider said, once Trump withdrew troops, “there was nothing left to do.”

Russian President Vladimir Putin and Turkish President Recep Tayyip Erdogan met in Russia this week, where they agreed to jointly patrol the Syrian border against Kurdish fighters, deepening the unlikelihood of European involvement and securing a major win for each of them, as Erdogan inches closer to his objective of pushing back the Kurds and Putin secures an outsize role in the future of Syria.

But that leaves Europe even more irrelevant in the region.

“I don’t think the E.U. or any other European country has a great plan to suggest,” Jim Townsend, the former deputy assistant secretary of defense for European and NATO policy, told Today’s WorldView. In recent weeks, he said, there has probably been even more increased caution over a new approach due to fears that Trump could quickly change U.S. policy as he has in the past. “No European wants to find out a week later that the rug has been pulled out from under them because Trump tweeted something else.”

After announcing the withdrawal of U.S. troops, Trump wished anyone who wanted to help protect the Kurds well, noting on Twitter that he hopes “they all do great, we are 7,000 miles away!”

Europe’s geographical proximity to Syria is in fact adding to Europeans’ anxieties. Many suspected fighters and their families being held in prisons and detention centers in Kurdish-controlled areas are European citizens, spreading concerns that if they were to escape, they could end up back in Europe without a proper vetting process. European countries are also eager to avoid more mass displacement in Syria that could lead to another major refugee crisis in Europe.

But Europe has “no plan on paper and no leverage,” Townsend said. “The people calling the shots are the Russians, Iranians, Turks and Assad.”

Michael Birnbaum in Brussels contributed to this report.

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