Founded in Egypt in 1928, the Muslim Brotherhood sought to create an Islamic state in that country, combat Western influence, and oppose secular democracy as well as secular authoritarianism. It was also, and still is, viciously anti-Semitic. Since then the Brotherhood has spread throughout the Muslim world, with branches—of which Hamas is one—from Morocco to Indonesia. Jonathan Schanzer, testifying before Congress, describes the nature of the organization and the threats it poses, and outlines how the U.S. could work against it.

President Barack Obama’s director of national intelligence, James Clapper, in 2011 . . . declared that “the term ‘Muslim Brotherhood’ . . . is an umbrella term for a variety of movements—in the case of Egypt, a very heterogeneous group, largely secular, which has eschewed violence and has decried al-Qaeda as a perversion of Islam.” Clapper eventually retreated on this point, and for good reason. The Brotherhood is not a patchwork of disparate groups, nor is it secular. It is not exactly heterogeneous, either. Many Muslim Brotherhood branches subject their members to rigid indoctrination processes and vet their members for their commitment to the organization’s ultimate goal, which is to empower the Brotherhood’s politicized and deeply intolerant interpretation of Islam.

Still, the Brotherhood’s various branches differ in terms of the tactics that they use to spread and empower the organization’s totalitarian ideology. In places like Tunisia and Morocco, the group has become an accepted element of the ruling elite. In places like Jordan, it has an uneasy modus vivendi with the government, fulfilling the role of the loyal opposition. In Egypt, the Brotherhood won elections following a dramatic popular revolution but was soon the target of a second mass uprising and a subsequent military coup. In the Gulf monarchies, the Brotherhood is viewed as an existential threat to the ruling regimes. . . .

Sanctioning the entire Muslim Brotherhood—as some have called for—would be difficult, if not impossible. . . . [T]he Brotherhood appears homogeneous in its adherence to a hateful, bigoted, and radical ideology, but it remains heterogeneous when it comes to violence. The right move is for the U.S. Treasury to take the lead in targeting overtly violent factions and those that finance terrorism. . . .

In addition . . . , the U.S. should also engage the Brotherhood’s two top state sponsors: Turkey and Qatar. Both countries are understood to be U.S. allies. Yet both continue to support a movement that is anti-American and extremist at its core. Turkey’s [ruling] Justice and Development party (AKP) is effectively the Turkish arm of the Muslim Brotherhood. . . . Qatar is undeniably the world’s most welcoming and generous jurisdiction for the Muslim Brotherhood. The relationship began in the early 1950s when the tiny emirate “provided a lucrative, stable, and welcoming platform where Brotherhood members could safely base themselves, recruit fellow members, and prosper.” In the 1960s, the Brotherhood began to use Qatar as a “launching pad” for expansions into other jurisdictions, like the United Arab Emirates.

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.