For starters, the question is whether an Iran with a nuclear capability would act as a rational state. If it were impossible to deter Iran's leaders from firing nuclear bombs at Israel, since their deliberations and decisions would be irrational, a nuclear Iran would indeed pose an existential threat to Israel, one that Israel could never countenance.

Under such circumstances, there would apparently be no choice but to try to destroy Iran's nuclear program. In contrast, if we assume that the political leaders and ayatollahs in Tehran are rational, we could rely on Israel's deterrent powers and live under the shadow of an Iranian bomb.

Israel's policy makers now face a complicated dilemma. Should they work based on the assumption that mutual deterrence of the Cold War variety is applicable to the Iranian situation? Will the calculations of a Muslim leader in Tehran be similar to those that were made in the Kremlin? Are Ayatollah Khomeini's successors willing to commit suicide and bring ruin to the Iranian people solely to kill a few hundred thousand inhabitants of the detested Zionist entity?

Prof. Ofira Seliktar of Gratz College in Pennsylvania examined the vast literature on this subject and found that two-thirds of researchers fall into the "nuclear optimist" category - they believe that a nuclear Iran would behave as a rational state and thus be susceptible to deterrence aimed at stopping it from using nuclear weapons. The rest are "nuclear pessimists." They believe that Iran is not a rational state, so deterrent capabilities will not suffice.

An analysis of the evidence reveals that the optimists defend their position much more convincingly. Iran, they contend, is developing nuclear weapons as a result of its bitter experience in the Iran-Iraq War in the 1980s, not because of a plan to use such weapons against its neighbors or Israel. The development of nuclear weapons is a rational Iranian choice; it's the logical response of a non-Western state to Western powers and their allies. (It's no accident that Defense Minister Ehud Barak quipped that if he were an Iranian, he would take part in the development of nuclear weapons. )

The possession of nuclear weapons might actually encourage moderation in the Iranian regime, just as China's Communist regime, which was considered radical and dangerous, became more cautious in the 1960s after it stockpiled nuclear weapons. As with any regime, the main goal of Iran's leaders is to remain in power; survival is the supreme objective of leaderships even in rogue states. It seems the pessimists exaggerate when they attribute irrationality to Iran's leaders. Those who talk about the "crazed dictatorship of Tehran" ought to recall the "crazed" dictators of the Cold War - Stalin and Mao, who acted in an entirely rational manner when it came to nuclear issues.

History teaches that the Iranian leadership behaves in a completely rational way when it might pay a very steep price for using military force. Thus, even the Ayatollah Khomeini, perceived as the quintessentially irrational leader, acted in a completely rational way when the Iraqis fired ballistic missiles at Tehran, claiming the lives of thousands of Iranians.

Khomeini, who had declared that he would never sign a cease-fire with Iraq, not before Baghdad agreed to an unconditional surrender, was compelled to come to terms with the new situation of bombs falling on Iran's capital, so he signed a truce with Saddam Hussein.

We should therefore note Israel's error when it magnifies the Iranian threat and depicts it as an existential threat. Israel's deterrent capability suffices to prevent any Iranian leader from entertaining thoughts about firing a nuclear warhead at it. The time has come to stop complaining about the boogeyman of existential threat and desist from jingoistic declarations that sometimes create a dangerous dynamic of escalation.

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