Blasted by mainstream leaders and embraced by the far right, the temporary U.S. travel ban has touched a raw nerve in Europe, before elections in several key European countries where immigration and security are hot-button topics.
Some point to the border walls that have sprouted across the region and a controversial deal struck with Turkey as testament to the European Union's own fractured response to immigrants and asylum seekers.
The European Union "is not in a good position to give opinions about the choices of others," Italian Foreign Minister Angelino Alfano told the Corriera della Sera newspaper this week.
Populist parties in Italy, which like Greece has faced waves of asylum seekers from Africa and the Middle East, see things differently.
"Only feminists, lawyers, dwarfs and ballerinas" are against the U.S. ban, said Forza Italia party member Maurizio Gasparri.
Washington says the temporary ban targeting Iran, Iraq, Syria, Yemen, Libya, Somalia and Sudan aims to give U.S. officials time to set up stronger screening procedures against potential terrorists.
Threats within borders
But a sizable chunk of Western Europe's security threat is homegrown, experts note.
In the case of the 2015 Paris attacks, "the perpetrators were born here and went through our public school system," said far-right expert Jean-Yves Camus. "They didn't come from Afghanistan or Syria. They wanted to take revenge on France, on a country they were citizens of."
That has not stopped right-wing parties from hailing the U.S. ban and calling for similar measures in Europe.
"Well done @Potus it's the only way to stay safe," tweeted Geert Wilders of the Dutch far-right Freedom Party, whose popularity is surging before March elections.
In Germany, which weathered several terror attacks, the right-wing National Democratic Party hailed the ban as barring "pseudo refugees and Muslims."
Meanwhile, in France, where far-right leader Marine Le Pen is expected to finish first in April's first round of presidential voting, a senior member of her National Front party suggested the country should follow America's example.
"Why not?" FN Vice President Steeve Briois told Agence France-Presse.
On Wednesday, Le Pen's campaign chairman, David Racheline, dialed back the remarks, saying a travel ban was not the party's top priority.
"We only said it was possible to do," Racheline told French radio. "What we want to do first is re-establish our borders."
More practically, said expert Camus, a travel ban would be unworkable in France, where members of a large ethnic North African community regularly travel back and forth to their homelands.
But calls for immigration curbs are resonating in France and elsewhere in Europe. An August Ipsos poll found that 57 percent of French believe there are too many immigrants here already; more than six in 10 believe refugees are unable to integrate.
Jean-Francois Dubost, who heads Amnesty International France's population protection program, thinks those statistics tell only part of the story.
"People are confused about the difference between immigrants and refugees," Dubost said.
While many French support the rights of those fleeing war and terrorism, he said, many also say in surveys that France cannot handle more refugees. "But they cite economic concerns," he added, "not security ones."
Europe's immigration record also reflects the gap between rhetoric and practice. While Germany has welcomed hundreds of thousands of asylum seekers, a policy that has cost Chancellor Angela Merkel voter support, others have failed to live up to their refugee promises.
Smaller numbers, border fences
France, for example, has resettled only about 5,000 of the 30,000 asylum seekers it vowed to take in from Greece and Italy. Others, like Austria, Hungary and Macedonia, have built border fences.
On the whole, Europe has been "a lot more generous" than the United States in taking in refugees and migrants, said Ian Bond, director of foreign policy at the Center for European Reform in Brussels.
"We've been more generous in the amount of money given to support refugees in the Middle East and also in the number of people entering Europe," he added. "So Europe still has some moral standing to say, 'We've done our best to cope with the refugee crisis in the Middle East.' "
Yet he thinks Europe, too, will try to intensify surveillance cooperation and vetting mechanisms to weed out and send back potential terrorists, such as the Tunisian author of December's Berlin attack.
"How do we make sure we remove these people, but still keep our doors open to people who have a well-founded fear of persecution and deserve asylum?" he asked. "That's a hard balance to strike."