This piece originally appeared in The Atlantic.

On October 28, 2018, I was at home in Paris, a blissful bubble, feeding my one-month-old baby girl, when I got the news of the massacre of Jewish worshippers at the Tree of Life synagogue in Pittsburgh. One thought repeated in my head: That’s it. A haven for Jews in the diaspora doesn’t exist anymore. I had feared for years that this moment would eventually arise, when the cancer of antisemitism would spread to liberal democracies around the world, including to the one place that had always seemed safe to me: the United States of America.

In France, the disease started nearly 20 years ago. The first antisemitic murder occurred in 2003. Sebastian Sellam, a young French DJ, was killed by his childhood friend, who shouted after the murder, “I killed my Jew! I’ll go to heaven! Allah guided me!” Since then, 14 other French Jews have been killed simply because they were Jews. In 2018, there was a 74 percent spike in antisemitic hate crimes, followed by another 27 percent increase in 2019.

Meanwhile, in Germany, antisemitic incidents increased so sharply that the country’s antisemitism commissioner, Felix Klein, issued a regrettable caution about the dangers of wearing a kippah in public. In the United Kingdom, each of the past three years has brought a new high in antisemitic incidents. The U.K. Equality and Human Rights Commission has launched an investigation into the Labour Party for “institutional antisemitism,” and many Jewish members have left the party.

The picture is depressingly grim across the European continent. Seeing a similar phenomenon arise in the U.S. feels for many European Jews like a scary déjà vu, confirming to Jews on both sides of the Atlantic just how bad the situation has become.

Two recent studies from the American Jewish Committee—one in France with the Foundation for Political Innovation, a French think tank, and one in the U.S. with SSRS, a leading polling firm—showed heightened anxiety among Jews. In France, 70 percent of Jews have personally experienced antisemitism, while in the U.S., a staggering 35 percent of the Jewish population reported that they had been the target of anti-Jewish hatred over the past five years.

A third of the respondents, both in France and in the U.S., said that they had taken concrete steps to hide their Jewish identity, including not displaying visible Jewish symbols and refraining from wearing traditionally Jewish clothing in public.

The question in Europe, and also in the U.S., is: Why is this happening now?

The causes are multiple but, most important, the rising antisemitism seems to be the symptom of a crisis in the current system of liberal, pluralist democracies around the world. Democracies thrive on shared values, political debate, and compromise. Majorities and minorities must respect one another. And everyone, while leaving space for debate, should at least rally around a shared vision, finding ground for common ideals rather than focusing on divisions

But unfortunately, we are living in a time of identity politics, conspiracy theories, and lies. The ties that once united our societies—truth, an idea of the common good—are falling apart. Dialogue and compromise, the essence of our communities, are dysfunctional. Radical rhetoric on the left and the right is the political language of the day, aided—and, one might even argue, provoked—by the echo chambers of Big Data and social media.

Extremists, whether religious or political, subscribe to exclusive ideologies based on the conviction that they possess the absolute truth. At a time of instability and change, they are looking for purity and authenticity, as the French author Marc Weitzmann has argued. Whether for Islamists striving for religious purity, the far right striving to be “true Americans” or “true Germans,” or even the far left seeking to rid the world of “imperialists,” Jews are and always have been the perfect scapegoats.

In Europe, just as in the U.S., antisemitism is multifaceted. It is entrenched in parts of the left where an irrational aversion to Israel can lead to the embrace of antisemitic tropes. Jeremy Corbyn’s Labour Party in the U.K. provides one example; statements made by Representative Ilhan Omar of Minnesota provide another.

As the former British Labour member of Parliament Ian Austin recently said in an interview with James Kirchick: “The idea that an institution as robust as the Labour Party and as important to Britain’s democracy could be so vulnerable to takeover by extremists and racists was unthinkable. But that should serve as a stark warning to people in the states that if that can happen in the Labour Party in the U.K., it can happen here.”

In this context, it can lead to a situation where antisemitism can also come from those who have made their objective protecting minority rights. The French historian Pierre-André Taguieff defines this new Judeophobia as an ideological framework in which Jews are no longer seen as an enemy race, but as a people conveying the putatively racist ideology of Zionism. This allows the battle against Jews to be presented as part of an antiracist or antifascist agenda, leading them to be excluded and sometimes even targeted.

The second source of resurgent antisemitism comes from the far right, with the proliferation of white-nationalist conspiracy theories as well as revisionist Holocaust-denial writings online and off. Although the growing populist movements on both sides of the Atlantic are not antisemitic at first glance, they often play with a certain sense of ambiguity, never entirely pushing away their antisemitic followers.

And finally, in Europe more so than in the U.S., a dramatic increase in antisemitism comes from within minority groups, in particular from within parts of Muslim communities. Nearly all violent antisemitic attacks in Europe over the past 20 years have been committed by jihadists.

Antisemitism can be understood only with this multifocal lens, keeping in mind that the varied sources often are interconnected. Take, for example, the “day of anger,” a demonstration that took place in Paris in 2014. An odd assortment of people—“ultra-Catholics” opposed to the idea of same-sex marriage; the far right; elements of the far left; and young people from immigrant backgrounds—demonstrated against the government of François Hollande. Some shouted “Jews, out of France!”and,“Jews, France is not yours!” providing a sad reminder that people who have nothing in common can and do come together in their hatred of Jews.

The most important lesson of the European experience for the U.S. is the need to analyze and confront all forms of antisemitism without exception, and to depoliticize the problem entirely. Europe wasted many years by not addressing the more contemporary forms of antisemitism, because it was politically uncomfortable to do so. It was difficult for many to realize and then admit, for example, that antisemitism could come from individuals who themselves were suffering from discrimination.

Learn How to Expose Antisemitism

Those willing to combat antisemitism only when it stems from their opponents, while rationalizing the phenomenon when it comes from their own camp, are not helping. They are merely playing a political game. Only an approach that fights all forms of hatred against Jews in equal measure can be effective.

Europe also holds other lessons for the United States, some drawn from the mistakes it made in confronting antisemitism. We in Europe have suffered from the lack of an effective political response to increasing antisemitism. Too many years have been wasted during which politicians first denied, then hesitated, and finally paid lip service before realizing that the problem had grown to such magnitude that it had become difficult to reverse the tide. Public authorities must instead unequivocally condemn antisemitism and its proponents when it first surfaces, prepare a clear action plan, and commit the necessary resources to fight this disease.

Additionally, the U.S. needs a genuine reappraisal of its approach to understand how it got to this point. Different forms of antisemitism sometimes need different approaches. Public policies need to be adapted accordingly.

In addition, successfully combatting antisemitism will require wide engagement with civil society. The Jewish community in Europe spent many years feeling entirely abandoned by the rest of society. We marched in the streets of Paris and Toulouse, but mostly alone. The reality is that antisemitism is not the problem of Jews alone. It is the problem of society as a whole. Jews are only the sentinels: antisemitism is a vicious disease that, if left unchecked, will spread and destroy everything that comes its way. Only when different parts of society come together—when difficult dialogue happens, whether between the right and the left or Jews and Muslims—can antisemitism effectively be countered.

And without abandoning the First Amendment, the U.S. must counter hate speech on the internet and social media. The internet should no longer be a wild west where hate propaganda is poured into the public sphere with impunity. Several studies have demonstrated the role of social media in the increase of hate crimes. We must understand that words can kill.

Finally, responses to antisemitism need to deal with some of its underlying causes. Moderate politicians on the right and the left must work to repair the social contract, to address the most difficult contemporary issues that populists and extremists tend to exploit, and to develop new forms of democratic debate and governance.

As a European engaged around the clock with American Jews, I feel a sense of responsibility and urgency to share our experience.

With every exhausting debate over what constitutes antisemitism, with every refusal to take into consideration antisemitism from the other side of the political divide, with every glance at the overwhelming amount of antisemitic hate speech online, and every time I see certain politicians in the U.S. fail to find the courage to speak out clearly and unequivocally and come up with a clear plan to combat this cancer, I get more nervous.

We have come to understand that no single country is immune to antisemitism. Europe’s experience offers a cautionary tale for the United States.

Simone Rodan-Benzaquen is the director of the American Jewish Committee (AJC) Europe.