For most of us, there is a reflexive tendency to think of anti-Semitism as something that is propagated by the alt-right: white supremacists, the KKK or neo-Nazi groups. That version of anti-Semitism was on full display during the violent protests last year that rocked Charlottesville, Va. For us, Charlottesville was like muscle memory. We’ve seen it before and know exactly what it means.

But what happens when the hate comes from somewhere unexpected, somewhere much closer to home? What happens when it comes from your friends and allies, and is disguised as something else?

This new form of anti-Semitism, which is being propagated by elements of the far-left, has a name: I’m talking about the pseudo-academic concept of “intersectionality.” It’s one of the most significant challenges facing our community.

Intersectionality is the radical academic theory that holds that all forms of social oppression are inexorably linked. It has become a code word for anti-American, anti-Western, anti-Israel and anti-Semitic bigotry.

And God said to Noah: “The end of all flesh has come before Me, for the earth has become full …

Nowhere has adoption of this radical paradigm been more pronounced than on American college campuses where, in the name of “identity politics” and “solidarity,” intersectionality has forced artificial coalitions between causes that have nothing to do with each other, except a hatred for their fellow students who are “privileged” because they are white, heterosexual, and especially, Jewish.

And that’s exactly what makes this form of far-left anti-Semitism so dangerous and so insidious; it is cloaked in the language of progressive idealism, and is far more nuanced than traditional alt-right anti-Semitism.

Let me provide you with some examples.

Linda Sarsour is an intersectional feminist and one of the organizers of the Women’s March on Washington. She openly supports anti-Israel Muslim groups that tolerate, if not accept, “honor killings” and genital mutilation of women. Because of her association with the Women’s March and other causes, however, Sarsour is viewed by many as a legitimate representative of the oppressed and disenfranchised.

Here’s the truth: Sarsour is an anti-Semite and BDS supporter, who once posed for a photo with a former Hamas operative. She often uses the hashtags #BDS and #FreePalestine on her tweets, and once tweeted that “Nothing is creepier than Zionism.” Sarsour has encouraged Muslims not to “humanize” Israelis and charged that there is no room in the feminist movement for those who support Israel’s right to exist.

Imagine if Sarsour had made those comments about any other minority. The left would be up in arms. But Jews are the wrong sort of victim.

Similarly, Jewish Voice for Peace—an organization that calls for “an end to violence against civilians, and peace and justice for all peoples of the Middle East”—invited Rasmieh Odeh, a member of the Popular Front for the Liberation of Palestine and a convicted terrorist, to appear as a speaker at its national conference. The idea of Odeh, a terrorist who quite literally has blood on her hands, speaking for a Jewish organization that claims to propagate peace, flies in the face of logic.

And if that doesn’t scare you, then all you need to do is take a close look across the Atlantic to see where all this can lead. In United Kingdom, the “Corbyn-Effect” has sent extreme anti-Jewish and anti-Israel sentiments from the obscure fringes of the political spectrum into the mainstream. That virus has already reached the shores of the United States, and is metastasizing rapidly.

If you think that I’m exaggerating the problem, then just think about Ilhan Omar, a Democrat in Minnesota’s House of Representatives, who tweeted: “Israel has hypnotized the world, may Allah awaken the people and help them see the evil doings of Israel,” which she described as “Satanic.” Ms. Omar is all but certain to win a U.S. Congressional seat in November.

As our community searches for an answer, we should ask ourselves an important question: How many of us were more disturbed by U.S. President Donald Trump’s silence in the wake of Charlottesville than we were at finding out that two leaders of the Women’s March—Linda Sarsour and Tamika Mallory—are hardcore anti-Semites who despise Israel?

Yes, that’s an uncomfortable question, but it needs to be asked because our enemies on both the left and the right would like nothing more than to see us fight among ourselves. It’s called divide and conquer, and it’s happening right before our very eyes.

The U.S.-Israel relationship works because of shared values, shared interests and a bipartisan consensus that Israel is an important friend and ally.

People may have strong feelings about Trump or Israeli Prime Minister Benjamin Netanyahu, but that should be irrelevant to their support for Israel. There is only one Israel, and we don’t have the luxury of being supportive one year and not the next.

Half or more of the Israeli public voted against Netanyahu, and yet Israel still needs foreign aid, still needs the Iron Dome defense system to protect its population against rocket and missile attacks, and still needs our support at the United Nations to counter the world body’s relentless attacks against the Jewish state.

Judging Israel over the Israel-Palestinian conflict—or because politicians in Israel from left to right agree with the decisions Trump is making—is more about our own self-centered issues. And while the rest of the world is busy telling the worst version of the truth blended with lies, the left in this country is making Jewish kids uncomfortable in their own skin—not because of the reality in Israel, but because people here won’t call out the lies from our own politically driven community.

This trend can’t be allowed to continue. Make no mistake, this is a war for the soul of the progressive movement.

Joshua S. Block is CEO and president of The Israel Project. He is a former Clinton-administration official and spokesman at the State Department’s USAID. He got his start on Capitol Hill in the office of Sen. Edward M. Kennedy and was a spokesman for the Clinton-Gore and Gore-Lieberman presidential campaigns. Follow him on Twitter: @JoshBlockDC.