Responding to the argument that it would be better for the West to contain rather than trying to destroy Islamic State (IS), Eran Lerman makes the case for defeating the caliphate decisively and completely:

The Islamists’ claim to supremacy depends not on the quality of their religious interpretation but on the force of their actions. Whereas Shiite traditions sanctify losers in battle, Sunni [traditions] do not. Total defeat on the field of battle would thus lead to the collapse of the ideas for which IS stands.

As for Iran, the continued existence of IS and its horrors is a gift to Ayatollah Ali Khamenei. He uses it to lure Turkey, blame the Saudis, and justify the ravages inflicted on Sunnis in Iraq and Syria by Iran’s proxies. . . .

There are also [groups fighting IS] that deserve [Israel’s] support and sympathy, and the overt assistance of Western powers. These are the Kurds, and even more so the Yazidis, who are marking the second anniversary of the massacres perpetrated against them by [Abu Bakr] al-Baghdadi’s butchers. . . .

In the case of IS, moral imperatives and realist calculations need not contradict each other. . . . Paraphrasing the Roman senator Cato the Elder [speaking of Carthage], it makes strategic and moral sense to say: Raqqa delenda est, i.e., the capital of IS needs to be taken and the organization destroyed.

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.