Over the years, Americans have come to discount statements on Israel and Zionism by Iran’s President Mahmoud Ahmadinejad. Repetition has rendered them unremarkable.

Israel must be “wiped off the map.” Zionism is a “germ of corruption” that “will be wiped off the face of the earth.” It is a “cancer cell” that must be “removed from the body.” The Zionist regime is “heading toward annihilation.” “They should know that they are nearing the last days of their lives.” “Israel is destined for destruction and will soon disappear.”

One is tempted to add: blah, blah, blah. It is easy to dismiss this rhetoric as being designed for domestic consumption. And soon after Iran’s June election, Ahmadinejad will be out of a job — history’s most persuasive argument in favor of term limits.

But the problem is this: Ahmadinejad’s language is not exceptional within the Iranian regime.

Iran’s supreme leader, Ayatollah Ali Khamenei, also has referred to Israel as a “cancerous tumor.” “The perpetual subject of Iran,” he has explained, “is the elimination of Israel from the region.” “There is only one solution to the Middle East problem, namely the annihilation and destruction of the Jewish state.” In recent weeks, Khamenei has promised, if the Iranian nuclear program is attacked, to “level down Tel Aviv and Haifa.”

Senior Iranian military leaders, presidential advisers and religious authorities can be quoted endlessly in a similar vein. Zionists are “microbes” and “bacteria” and a “cancerous growth.” “Jews are very filthy people,” who are responsible for spreading disease and drug abuse. There is a religious duty to “fight the Jews and vanquish them so that the conditions for the advent of the Hidden Imam will be met.”

Such arguments are deeply embedded in the Iranian regime — as a statement of mission, an organizing principle. This won’t be changed by a single election.

It is possible to overplay such rhetoric. The Iranian government is not simply an irrational, apocalyptic cult. It may eventually respond to sanctions. It is sometimes necessary for America to engage in diplomacy with very nasty people.

But it is possible to underplay this language as well. It is not merely hate speech. It has the hallmarks of incitement to genocide: the dehumanization of a targeted group and the use of code words to cover genocidal intent. (In Rwanda, Tutsis were described as “snakes” and “cockroaches” who should be sent “down the river.” The rivers were eventually clogged with corpses.)

One interesting theoretical question: Is such Iranian rhetoric a crime under the Genocide Convention of 1948 — to which Iran is a signatory — which forbids the “direct and public incitement to commit genocide”? The language of Iranian leaders is certainly direct and public. When forced to defend themselves, they often claim (unpersuasively) that their target is Zionists rather than Jews. But in the determination of genocidal intent, this doesn’t matter. Genocide can be directed against any group — racial, ethnic, religious or national.

Yet the (rather thin) case law on incitement to genocide also requires an imminent threat of violence from the audience. In the Iranian case, the threat comes from government action — providing long-range missiles to Hamas or (down the road) the use of nuclear weapons.

In any event, a prosecution of Iranian officials for incitement to genocide is an exceedingly theoretical prospect, since it would require a referral from the U.N. Security Council — something Russia and China, which hold vetoes in that body, would not entertain.

But Iranian incitement should not be glossed over. It is not common, culturally excusable or normal among nations. “How many other states do we know,” asks Michael Abramowitz, director of the Center for Genocide Prevention at the U.S. Holocaust Memorial Museum, “that talk about other human beings in the way the Iranian leadership speaks of Israelis and Jews? They are conditioning generations of young people in their own country and the broader Middle East to think of Jews as subhuman, which makes acts of terror by groups like Hamas and Hezbollah seem more thinkable.”

Several years ago, during an Iranian military parade, a Shahab-3 missile was decorated with the banner: “Israel must be uprooted and wiped from [the pages of] history.” This can’t be reasonably construed as a vivid political metaphor. It is the depiction of a twisted ideal, broadly shared within the Iranian regime. And it is one reason that President Obama is right to draw his red line. Such a banner must never hang on an Iranian nuclear weapon.

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