In Modern Orthodox Judaism: A Documentary History, Zev Eleff for the first time has collected the source materials necessary to understand the development of a denomination that, although its adherents account for under 10 percent of affiliated American Jewry, now plays a disproportionate role in American Jewish life. Daniel Ross Goodman praises the book, while noting some serious gaps:

The history of self-consciously “modern” Orthodoxy is inseparable from the history of Yeshiva University, which is a product of the early 20th century. Eleff covers Yeshiva University’s birth, development, and evolution. . . . Of course, the book also contains several key statements from Modern Orthodoxy’s most outstanding spokesmen: the great halakhist and thinker Rabbi Joseph B. Soloveitchik, [the movement’s most prominent rabbi until his death in 1993], and Rabbi Norman Lamm, who served as the president of Yeshiva University from 1976 to 2003. . . .

Although Rabbi Lamm has been a central figure of inestimable importance to Modern Orthodoxy for nearly seven decades, graduates of Yeshiva University, and anyone even tangentially connected to the institution, are well aware of the fact that it has not been Lamm but rather Yeshiva University’s rashey yeshivah—authoritative halakhists and brilliant talmudists like Hershel Schachter, Mordechai Willig, [and others]—who have, arguably, had a more direct impact on the lives of thousands upon thousands of American Modern Orthodox Jews. It is surprising then, that a volume that features so many texts related to Yeshiva University all but completely excludes figures who can be said to have been the university’s most influential rabbis.

When it comes to Modern Orthodoxy’s present challenges, Goodman finds Eleff better attuned:

The ideology of Modern Orthodoxy, undergirded by Soloveitchik’s distinctive blend of existentialism and neo-Kantianism, is a difficult one to grasp. Most people prefer clear lines and black-and-white differentiations to living with complexity, and it doesn’t help matters that even many of those rabbinic leaders who understand Soloveitchik’s philosophy and embody its values, like Rabbi Lord Jonathan Sacks, do not identify themselves as Modern Orthodox.

This, combined with growing pressure from its right and left flanks, the prohibitive cost of Modern Orthodox life, widespread theological uncertainty, and a continuous “brain drain” in which many of the most committed American Modern Orthodox Jews leave for Israel—Modern Orthodox Jews have the highest rates of aliyah among all American Jews—means that the movement’s future will likely be as ambiguous and complicated as its complex, tension-filled philosophy.

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.