Saul Freeman, a lifelong supporter of Britain’s Labor party, writes of his shock at the growing hatred for Israel in its ranks, which is often indistinguishable from pure anti-Semitism. The recent selection of Jeremy Corbyn—a parliamentarian unapologetic about meetings with his “friends” from Hamas and Hizballah—as the party’s leader made the problem clear:

[M]y wife and I . . . are of the left, but are no longer welcome, unless we become “good Jews” who are not “bad, Zionist Jews.” We worry about our son. He will be confronted by “Israeli Apartheid Week” when he arrives on a university campus in a few years. If he is a Jew who believes that Israel has a right to be, he will be hated by many on the student left. My son is an enthusiastic, articulate, and kind boy. The realization that he will be hated by those who will not see any of these attributes, but instead will see only one attribute—his Jewishness—chills me.

Strangers feel compelled to say hateful things to me. Others threaten violence to all Jews—“go back to Auschwitz, Zionist scum.” All this from the left.

We slowly become traumatized by the sheer horror of what has unfolded around us. Mostly, we are distressed because we cannot understand why the left is so silent when Jews call out. . . . None of this makes sense. We have no critical lens through which to view this rupture. . . .

Two extraordinary events demonstrate something important about Israel’s most fervent adversaries. One was a speech given at something called The People’s Forum (funded generously by Goldman Sachs), which stated, “When the state of Israel is finally destroyed and erased from history, that will be the single most important blow we can give to destroying capitalism and imperialism.”

The suggestion that this tiny state is the linchpin of a global, centuries-old phenomenon like capitalism goes well beyond anything resembling rational criticism. Even if Israel were guilty of genocide, apartheid, and oppression—which of course it is not—it would not follow that its destruction would help end capitalism or imperialism.

The other was an anti-Israel protest that took place in front of New York City’s Memorial Sloan Kettering Cancer Center, deemed “complicit” in Israel’s evils. At organizers’ urging, participants shouted their slogans at kids in the cancer ward, who were watching from the windows. Given Hamas’s indifference toward the lives of Gazan children, such callousness toward non-Palestinian children from Hamas’s Western allies shouldn’t be surprising. The protest—like the abovementioned speech—deliberately conveyed the message that Israel is the ultimate evil and its destruction the ultimate good, cancer patients be damned.

The fact that Israel’s adversaries are almost comically perverse does not mean that they can be dismissed. If its allies fail to understand the obsessive and irrational hatred that it faces, they cannot effectively help it defend itself.