The historic churches of Europe are grand repositories of artwork, some of it among the world’s finest. But among these works is no small amount of anti-Semitic iconography, some of which is still venerated by the devout. Menachem Wecker writes:

In Seville, the Parroquia de San Nicolás de Bari, a small 18th-century church, contains a troubling altar. In a golden niche, a young boy, clad in a flowing white and red altar-boy rochet with a red ribbon beneath his chin, hangs crucified above a Madonna and child, sitting enthroned above a crescent moon. A label once identified the boy as Dominguito del Val, a legendary figure alleged to have been murdered by the Jews of Zaragoza. As with [another such] boy at [a] Toledo cathedral, this death—real or imagined—served as a pretext for a pogrom. . . .

The replacement label, however, still stated that the boy was crucified. . . . That [label] too was eventually removed, and when I visited the altar, . . . it was the only one in the church without any identifying text. . . . But now the plaque mentioning the crucifixion of the boy is back. . . . “Clearly, all the parishioners do think that not only he existed—no evidence of that—but also he was murdered by the Jews,” says Moisés Hassán-Amsélem, [a local Jewish tour guide who has campaigned for the altar to be removed]. “I very often see people praying in front of the altarpiece. They definitely consider him a saint.”

This conflict is local in nature, in some ways, but it raises broader questions about memory and history. To what degree, if at all, ought these [scenes] be remembered and memorialized? Should troubling traces of past violence and hatred be removed altogether, or, if they ought to remain as witnesses, how should they be contextualized? And what are the responsibilities of religious institutions in this regard? . . .

Some of the most egregious examples of anti-Semitic art appear in German prints, paintings and sculptures. Many German woodcuts, for example, depict horned Jews associating with devils and pigs. Some of these illustrations show Jews feeding at the anuses of large pigs. . . . This motif, called the Judensau, or “Jew sow,” received attention last year as Germany celebrated the 500th anniversary of the start of the Protestant Reformation. . . . St. Mary’s Church in Wittenberg, where Luther preached regularly and where he married his wife and baptized six of their children, contains a 14th-century sculpture of the Jew sow on its facade. . . . The sculpture is one of up to 200 on the theme made between the 13th and 18th centuries.

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.