President Obama and his supporters have censured Israel’s prime minister for his vocal opposition to the nuclear agreement with Iran, suggesting that he has severely violated diplomatic protocol. Alan Dershowitz writes that nothing could be further from the truth:

Benjamin Netanyahu is acting properly in lobbying against the Iran deal. And President Obama is acting improperly in accusing him of interfering in American foreign policy and suggesting that no other foreign leader has ever tried to do so: “I do not recall a similar example.”

President Obama is as wrong about American history as he is about policy. Many foreign leaders have tried to influence U.S. foreign policy when their national interests are involved. . . . Winston Churchill appeared in front of Congress and lobbied heavily to have America change its isolationist policy during the run up to World War II. Nor can President Obama claim ignorance about recent events, when he himself sent David Cameron, the prime minister of the United Kingdom, to lobby Congress in favor of the Iran deal. . . .

Prime Minister Netanyahu’s nation has a far greater stake in the Iran deal than most of the countries that negotiated it. But Israel was excluded from the negotiations. Any leader of Israel would and should try to exercise whatever influence he might have in the ongoing debate over the deal. . . . Does President Obama really believe that Israeli leaders are required to remain silent and simply accept the consequences of a deal that puts Israel’s population at risk? . . .

President Obama’s attack on Prime Minister Netanyahu, for doing exactly what he himself would be doing if the shoe were on the other foot, has encouraged Israel-bashers to accuse opponents of the deal of dual loyalty. . . . The president should stop attacking both the domestic and international critics of the deal and engage us on the merits.

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.