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At what point can an ideology be blamed for violence? After a horrific mass shooting at a Pittsburgh synagogue on Saturday, President Trump’s supporters seemed to say never.

They denied any link between the White House’s persistent, polarizing rhetoric and the slaughter that took place. They scoffed at claims that Trump’s demagoguery — replete with white-nationalist themes that critics have long cited as anti-Semitic in effect, if not intent — played a role in what was the most deadly act of anti-Semitic violence in American history.

“People on both sides of the aisle use strong language about our political differences,” said Vice President Pence in an interview Saturday. “But I just don’t think you can connect it to threats or acts of violence.”

But the White House cannot easily wave away its own responsibility for the anger roiling the nation. “Culpability is a tricky thing, and politicians, especially of the demagogic variety, know this very well. Unless they go as far as organized, documented, state-implemented slaughter, they don’t give specific directions,” wrote Julia Ioffe in a column for The Washington Post. “They don’t have to. They simply set the tone. In the end, someone else does the dirty work, and they never have to lift a finger — let alone stain it with blood.”

The gunman in Pittsburgh, suspected to be 46-year-old Robert D. Bowers, was apparently driven by an intense hatred of Jews and what he believed was their supposed role in destroying American society. His last message on a website popular among the far right accused liberal Jews of enabling caravans of migrant “invaders” to enter the United States. “I can’t sit by and watch my people get slaughtered,” Bowers is believed to have written just hours before he allegedly went on his murderous rampage.

The issue that allegedly drove Bowers to mass murder is one that Trump has turned into national news. While he apparently criticized Trump for accommodating what he reportedly called a “k--- infestation” — using a slur for Jews — in the United States, Bowers supposedly acted on the very fear the White House and leading Republicans have stirred up to rally votes.

Trump, his party and their allies in right-wing media framed a caravan of Central American migrants as an invading army. Though the group is weeks away from the U.S. border — and unlikely to actually cross it — it was cast as the most urgent threat to American security. Trump said the group was providing cover for dangerous “Middle Easterners,” scapegoating two sets of minorities at once. Right-wing commentators accused liberals, including Jewish American financier George Soros, of funding the enterprise to flood the country with illegal voters — the same multilayered, ultranationalist fever dream that terrified Bowers.

In the aftermath of the massacre in Pittsburgh, critics argue that such demagogic chickens are coming home to roost. “The numerous statements he’s made, calling himself a ‘nationalist,’ crowds at his rallies chanting threats against George Soros — it’s all connected,” Cecillia Wang, deputy legal director at the American Civil Liberties Union, told The Washington Post.

“Ordinarily, a politician cannot be held responsible for the actions of a deranged follower,” wrote the Atlantic’s Adam Serwer. But, Serwer observed, Trump is no ordinary politician. He has winked encouragement to neo-Nazis, spread dangerous conspiracy theories about ethnic minorities and political opponents, and at times even goaded supporters toward what could be described as vigilante violence. “Ordinarily, presidents do not blatantly exploit their authority in an effort to terrify white Americans into voting for their party,” wrote Serwer. “Trump did everything he could to fan the flames, and nothing to restrain those who might take him at his word.”

Of course, Trump is hardly the only politician to fan such flames. He has found common cause with a host of illiberal and right-wing leaders, as Deutsche Welle’s Martin Gak catalogued: “Europeans need to recognize similar anti-Semitic signs at home. Hungarian Prime Minister Viktor Orbán has pursued a plainly anti-Semitic electoral campaign that used Soros as the symbol of an anti-Hungarian globalist conspiracy. The leader of the far-right Alternative for Germany, Alexander Gauland, has vomited invective against the ‘globalized class’ that supposedly occupies positions in academia, media, finances and NGOs. The British euroskeptic politician Nigel Farage, echoing Henry Ford’s warning against the international Jew, recently told Fox News that George Soros was the ‘biggest danger to the entire Western world.’ Meanwhile, Italy’s far-right interior minister, Matteo Salvini, has railed against a financier whom he accused of wanting to ‘fill Italy with migrant slaves’ and bringing about the financial ruin of Italy.”

Set against this illiberal international are political parties and civil society groups that defend the values of a pluralist, inclusive society, including a number of influential Jewish American organizations. In his alleged social media post, Bowers singled out HIAS — an organization that for decades helped resettle Jewish refugees and now advocates for non-Jewish refugees — as a menace. Three years ago, as Trump’s campaign picked up steam on a platform to bar Syrian refugees from the United States, HIAS organized a petition signed by more than 1,000 American rabbis standing up for refugee rights.

“What does HIAS mean today? To refugees around the world, it’s become an international word for hope, in dozens of tongues and for numerous faiths,” wrote author Lev Golinkin in an op-ed for the New York Times. “To me, it symbolizes America — and Judaism — at its best. And it’s easy to see how HIAS stands for everything white supremacists hate: tolerance, understanding and empathy.”

In an era of nationalist identity politics, the group received criticism for diverting its resources to aid non-Jews — criticism it ignored. “We decided to help,” HIAS chief executive Mark Hetfield told Golinkin, “not because they are Jewish, but because we are Jewish.”

It is that belief in a common humanity that Trump and his allies seem to reject.

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