By Barry R. Posen

How Dangerous Is a Nuclear Iran?


James Lindsay and Ray Takeyh offer a carefully reasoned and persuasive argument that in the likely event that Iran gains a nuclear or near-nuclear capability, the U.S. government should adopt a policy of containment and deterrence. They outline the negative scenarios that might ensue if instead of pursuing such an effort, Washington simply let regional politics take their course. Although much of their analysis is correct, it has some peculiar qualities and offers some inconsistent advice.

The strangest aspect of the article is its alarmist and martial tone, which is at odds with its specific prescriptions. The authors grimly predict all the possible leverage that Iran would glean from having or almost having nuclear weapons and the negative consequences that the United States would suffer from its failure to stop Iran from obtaining such weapons. But the possible consequences of an Iranian nuclear capability are largely conjectural (save for one: nobody would think of invading Iran anymore). And oddly, Lindsay and Takeyh follow their warnings of dire outcomes with persuasive arguments about why they are unlikely to occur.

On the whole, Lindsay and Takeyh argue for prudent, low-key containment efforts and for resisting the urge to ramp up U.S. military deployments in the Middle East so as to avoid aggravating political sensitivities there. Yet the authors are willing to threaten preventive war for negotiating purposes, writing, "Military options to prevent Iran from going nuclear must not be taken off the table" -- even though they concede that a strike would accomplish little.

More ominously, Lindsay and Takeyh argue that Washington should be willing to threaten military action, including a nuclear attack, to deter a variety of Iranian actions, including the subversion of Iran's neighbors.

These tensions between cool analysis and saber rattling suggest less about the problem posed by Iran than about the difficulty of having a reasoned strategic discussion in Washington today; hawkishness is now the ticket for admission. The mood music around Lindsay and Takeyh's article sounds a warning about U.S. domestic politics: In the event that additional sanctions against < location>Tehran do not elicit its cooperation -- and they probably will not -- proponents of preventive war will reemerge from hibernation. Advocates of containment should prepare for a bruising political fight.

Lindsay and Takeyh should have reviewed how a U.S. or an Israeli preventive attack might unfold and the range of military, economic, and political consequences that could arise. They do note that such an attack would, at best, delay Iran's nuclear program even as it hardened the regime's commitment to it. An attack might also render the program and the regime more popular at home, and it could make Tehran more popular in some corners of the Arab world, where standing up to the United States or Israel has a peculiar cachet.

On the military front, Iran has a number of retaliatory options. None of them would be devastating, since Iran is not a very advanced conventional military power, but all would be troublesome: the harassment of tanker traffic in the Persian Gulf, damage to oil infrastructure, attacks on U.S. forces in Afghanistan and Iraq by Iranian operatives or proxies, and terrorist strikes worldwide. Although the United States and its allies could deal with such ripostes, there would be no obvious military strategy to bring even a desultory exchange of strikes and counterstrikes to an end. Any military activity in the region would roil the international oil market -- not least because such a conflagration would likely suspend Iran's oil exports. This would not be a catastrophic outcome, but it could be problematic given the present fragility of the global economy.

Of all these possibilities, the most disturbing are the political fallout in Iran and the Middle East, the possible attacks on U.S. troops, and the difficulty of ending even a limited war. The case for preventive war is even weaker when one considers that an attack could not end Iran's programs once and for all; in other words, neither the United States nor Israel would gain much from it. Washington's frequent statements that preventive war remains "on the table," a threat it hopes will support negotiations, may come back to haunt the U.S. government when its bluff is called.

Lindsay and Takeyh rightly argue that the threat of nuclear force must be part of the United States' strategy of containment and deterrence. But they overreach when they recommend that the United States engage in "military retaliation by any and all means necessary, up to and including nuclear weapons" if Iran attacks another country with conventional weapons; transfers nuclear weapons, materials, or technology; or steps up its support for terrorism and subversion. The threat of a nuclear response should be reserved for deterring crimes that involve using or threatening to use nuclear weapons. Iran would be a legitimate nuclear target if it tried to coerce its neighbors with nuclear weapons or if it gave nuclear weapons away to nonstate groups that then used them. But this is as far as Washington's nuclear threats should go; the punishment should fit the crime. Relying on nuclear weapons beyond this in the effort to contain Iran would undermine the United States' broader goal of limiting the political salience of nuclear weapons.

The United States and its allies do need to be able to threaten tough and practical responses to deter a range of dangerous actions by Iran. But these need not include nuclear threats because the threat of a U.S. conventional response is highly credible. If Iran invaded another country, its obsolescent conventional forces would be destroyed handily by the United States and its allies. And if Iran were to get into the business of exporting nuclear weapons or nuclear technology, it would suffer a range of damaging consequences, possibly including a military attack.

Most disturbingly, Lindsay and Takeyh recommend threatening nuclear retaliation to deter Iran from subverting its neighbors. But as their own analysis suggests, it would be very difficult to determine where to draw that "redline" because subversion is usually clouded in secrecy. Moreover, internal unrest in neighboring countries would likely have multiple causes, obscuring Iran's hand. Given the ambiguities and the gravity of any decision to use nuclear weapons, Iran would not likely be deterred by such a threat because the United States would be unlikely to carry it out. In any case, the United States and its friends have good intelligence agencies, and so they ought to be able to combat Iran's subversive activities directly. The provision of weapons, money, advice, and training are the tools of subversion; intelligence collection, covert interdiction, and overt police work are the countermeasures. Neither a conventional counterattack nor a nuclear response would be appropriate. And if Iran finds openings for subversion because its neighbors mistreat their own citizens or mistreat other states, perhaps domestic political or foreign policy reforms in those countries are in order, as the authors recommend.

Lindsay and Takeyh suggest that the United States should threaten nuclear preemption, writing that Washington should threaten to "strike preemptively, with whatever means it deemed necessary," in the event that Iran developed a nuclear force and put it on alert during a crisis. Although such a reaction would be unwise, both the United States and Israel would consider it, and Iran should know this. Nuclear alerts are a dangerous game. In any event, Washington and Tel Aviv should wield this threat with great care, lest mutual alarm prompt Iran to put its nuclear forces on alert out of fear, not aggressive intent, and noises about preemption provoke Iranian escalation. No one would want that to happen.

Realistically, neither the United States nor Israel ought to rely on preemption as the means to a meaningful victory in a nuclear war with Iran. Strategists should be honest: despite the United States' impressive capabilities and Israel's deep fears about Iran, the decision to use nuclear weapons to preempt a suspected attack from Iran would be very difficult. This is a long-standing problem. Even an extraordinarily successful preemptive attack might miss something, and the wounded and angry victim would probably respond. Unlike with conventional forces, in the world of nuclear forces, the remainders matter; even one surviving nuclear missile could destroy a city. This is an irreducible risk, and not even the expanded theater missile defense systems that Lindsay and Takeyh recommend would take it out of the calculation. Moreover, a decision to launch a nuclear first strike would sorely test not only the nerves of U.S. or Israeli policymakers but also their ethics. Intelligence indicating that Iran was preparing to launch its weapons is unlikely to be so compelling as to make a decision to use nuclear weapons for the first time since 1945 an easy one. Even conventional preemption is fraught with risk.

Iran must instead be made to understand one simple thing: using nuclear weapons first or arranging for others to do so would be the path to certain annihilation. There is nothing Iran could do to prevent devastating retaliation from the United States or Israel. Making that point clear should be the underpinning of the United States' deterrence strategy.

BARRY R. POSEN is Ford International Professor of Political Science and Director of the Security Studies Program at the Massachusetts Institute of Technology. He is currently on leave at the Dickey Center at Dartmouth College.


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