Five years ago, during an earlier Israeli operation in Gaza, the British novelist Howard Jacobson explained why “call[ing] the Israelis Nazis and liken[ing] Gaza to the Warsaw Ghetto” goes far beyond mere “criticism” of Israel:

Berating Jews with their own history, disinheriting them of pity, as though pity is negotiable or has a sell-by date, is the latest species of Holocaust denial. . . . Instead of saying the Holocaust didn’t happen, the modern sophisticated denier accepts the event in all its terrible enormity, only to accuse the Jews of trying to profit from it, either in the form of moral blackmail or downright territorial theft. According to this thinking, the Jews have betrayed the Holocaust and become unworthy of it, the true heirs to their suffering being the Palestinians.

Experts call this Holocaust inversion. Based in the claim that Israel now behaves toward the Palestinians as Nazi Germany behaved toward the Jews, it originated in post-World War II Soviet propaganda, and from there spread to the Soviets’ Arab clients. It is now fully embedded in the Arab-Muslim world, where it grows and mutates in symbiosis with outright denial that the Holocaust occurred or a radical reduction of its genocidal scale, ferocity, and number of victims. Holocaust inversion has a graphic omnipresence in cartoons all over the Arab and Iranian press, where Israelis are regularly portrayed in Nazi regalia. Elsewhere in the Middle East and beyond, it has surfaced in the rhetoric of populist demagogues and the media. In Turkey’s new president and long-time prime minister, Recep Tayyip Erdogan, it now has a champion in a head of state. In Europe, Holocaust inversion is busy spreading beyond its original locus of infection and finding a home among intellectuals and activists, especially on the Left.

Thankfully, the disease is still rather hard to find in America, where it festers in only a few dark places. Some of those places, regrettably, operate as institutions of higher learning, and in one of them—Columbia University—a number of professors, mainly instructors in Middle East studies, have distinguished themselves in the black art of defaming Israel as a Holocaust emulator. Only a decade ago, Columbia was compelled to investigate departmental instructors who had been accused of intimidating their students with extreme anti-Israel diatribes. Not only did the university absolve its professors, however, it even granted tenure to the one faculty member against whom its own investigators found a student’s claims to be “credible.” Encouraged by this green light, the extremists have been tunneling under Morningside Heights ever since, fortifying their positions and waiting for a signal to emerge firing...