Ideas. Action. Impact. The Washington Institute for Near East Policy The Washington Institute: Improving the Quality of U.S. Middle East Policy

Other Pages

Policy Analysis

PolicyWatch 1152

Iran: The Complex Calculus of Preventive Military Action

Michael Eisenstadt

Also available in

Policy #1152

September 25, 2006

Faltering diplomacy to suspend Iran's nuclear program -- highlighted by French president Jacques Chirac's September 18, 2006, call to temporarily suspend the threat of United Nations sanctions on Iran -- has revived speculation that the United States might undertake preventive action to thwart Iran's nuclear ambitions.

U.S. policymakers considering prevention face a range of uncertainties that greatly complicate their decision calculus. To some extent, their bottom line is likely to depend on how they weigh competing factors: What can prevention accomplish? Can the risks of Iranian retaliation be mitigated? Can the consequences of Iranian proliferation be managed? And can a nuclear Iran be deterred? Policymakers must also consider a number of other political and military-technical factors that are likely to complicate the calculus of prevention and to influence a decision to act.

Consulting Congress . . .

Although the U.S. Constitution invests in Congress the power to declare war, the practice in recent decades has been for the president to seek a joint resolution from Congress authorizing him, as commander-in-chief, to use military force to deal with major threats to international peace and security. Given that precedent, the need for secrecy to ensure a successful surprise attack, deep divisions in the body politic over the war in Iraq, and the Bush administration's penchant for pushing the limits of executive authority, the administration is likely to find itself on the horns of a dilemma: whether to inform a select, bipartisan group of members of Congress of its intention to strike just before doing so (thereby jeopardizing public support for subsequent measures against Iran), or whether to encourage Congress to openly debate the merits of military action (thereby precluding surprise, allowing Iran time to disperse and hide key elements of its nuclear program, and risking defeat of a joint resolution). How to handle the politics of preventive action could prove a major challenge for the administration.

. . . and Allies

Many U.S. allies stand to be adversely affected by Iranian retaliation for a preventive strike, which could, among other things, take the form of a global terrorism campaign. The United States therefore has an obligation to warn its allies in advance to prepare for the figurative "fallout" from a preventive strike. Because operational security considerations could preclude immediate advance warning, the United States should encourage its allies well ahead of time -- without implying that prevention is imminent or inevitable -- to take necessary measures to reduce their vulnerability to Iranian retaliation (e.g., by rolling up suspected Iranian agent networks, reducing staffing at their embassies in Iran, and taking steps to secure embassies and cultural centers located in third countries of concern).


If the United States were to strike, would sooner be better than later? At least three factors could influence the timing of an operation: the quality of the intelligence picture, the maturity of Iran's nuclear infrastructure, and the state of its scientific-technical human resource pool.

• The intelligence picture. By about 2004, the international community had a detailed picture of large parts -- perhaps the entirety -- of Iran's previously clandestine nuclear program, though some clandestine facilities may have remained undetected. Since February 2006, however, Iran has barred inspectors from the International Atomic Energy Agency from visiting sites other than those where safeguarded materials are present, thus raising the level of uncertainty regarding its nuclear program. New intelligence, however, could expose ongoing activities or previously undisclosed clandestine nuclear facilities in Iran. It is therefore impossible to assess, solely on the basis of publicly available information, how the passage of time is affecting the intelligence picture.

• The nuclear infrastructure. It would be desirable to destroy workshops engaged in the production of centrifuge components as soon as possible because of their potential to contribute to a clandestine program. Regarding major facilities, though some are complete (e.g., the conversion plant at Esfahan), others are in the early phases of construction (e.g., the centrifuge facility at Natanz and the research reactor at Arak). Striking facilities that are in the early phases of construction now would yield little benefit; it would make sense to wait until they are closer to completion, although protective measures at these sites might well improve with the passage of time.

• The scientific-technical human resource pool. Much of the talk about preventive action focuses on striking facilities, but people are the backbone of the program. Finding a way to neutralize key scientists, engineers, and project managers (by encouraging them to emigrate or by other means) is critical to successful prevention. Here, sooner is clearly better than later, for with the passage of time, these individuals gain experience and know-how, which they are likely to share with other Iranian -- and perhaps foreign -- colleagues.

In sum, because these factors are moving along independent and, in some cases, contradictory timelines, an optimal moment to strike may not occur; successful prevention could require intermittent strikes (in combination with other measures) against various target sets over a period of time.

Target Intelligence

Accurate target intelligence is the sine qua non of effective preventive action. On the one hand, because of the risks preventive action would entail -- and in light of intelligence failures regarding weapons of mass destruction in Iraq and elsewhere -- policymakers will likely set a high bar for action. On the other hand, the intelligence community has chalked up a number of important successes uncovering nuclear programs in North Korea (1993) and Libya (2003), as well as the Abdul Qadir Khan nuclear supplier network (2003). Moreover, recent revelations about Iran's nuclear program apparently derived from leaks from inside the program. Thus, one should not dismiss the possibility that the intelligence picture concerning Iran's nuclear program could change rapidly, thanks to additional leaks.


Much has been made of the difficulty of destroying buried and hardened targets, and some have even claimed that nuclear earth-penetrating munitions (such as the B61 Mod 11 bomb) would be needed to destroy certain key facilities in Iran's nuclear program. In fact, the targeting of buried, hardened targets with either conventional or nuclear penetrator munitions involves tremendous uncertainties, such as the quality of the target intelligence, the configuration of the facility, its depth underground, the composition or geology of the overburden atop the facility, and the nature of hardening measures taken to protect it. Given what is know about Iran's principal declared centrifuge enrichment plant at Natanz (which is a relatively shallow "cut and cover" facility), it is possible that large conventional penetrator munitions would be up to the task of disabling or destroying the facility, even if repetitive strikes would be necessary to penetrate the overburden and burster slabs above the plant. At any rate, penetrator munitions are not the only way to deal with such facilities.

Measuring Success

Success in prevention would be measured primarily in terms of the delay imposed on Iran's nuclear program. For this reason, if the United States goes this route, a plan to make the most of the time gained by prevention (which might not meet expectations) is absolutely critical. Such a plan would hinge on nonproliferation measures to disrupt Iranian efforts to rebuild its nuclear program, accelerated efforts to promote regime change in Iran, or other steps. Failing to plan for how to best use the time gained by prevention would be an omission on the order of the failure to adequately plan for the aftermath of regime change in Iraq.

Information Operations

Washington must try to prevent Tehran from using the nationalist backlash that military action could engender, to undermine pro-American sentiment in Iran and consolidate popular support for an unpopular regime. Should the United States strike, it should explain to the Iranian people through a high-profile information campaign that its goal was to prevent the mullahs from obtaining "the bomb," which they would likely have used to fend off pressure for political change and to threaten regional peace -- with potentially dire consequences for the Iranian people. And it should couple strikes on Iran's nuclear facilities with strikes on headquarters and barracks of the Ministry of Intelligence and the Revolutionary Guard -- organizations that have ties to Iran's nuclear program and that are responsible for repression at home and terror abroad. Thus, attacks on Tehran's apparatus of repression, tied to a carefully crafted information campaign, might help mitigate a nationalist backlash against the United States and limit the regime's ability to exploit a backlash for its own purposes.


Even as it seeks a diplomatic solution to the current impasse with Iran, the United States should keep the option of military prevention on the table. Whether Tehran can be cowed by threats of preventive action is unclear; some Iranian politicians might even welcome an attack in order to use a nationalist backlash to bolster their domestic standing. However, the possibility of preventive action might help stiffen weak European spines and move Russia and China to lend greater support to sanctions and other, tougher measures. Finally, by creating an atmosphere fraught with uncertainty, the threat of prevention serves also to create an environment unfavorable to foreign investment in Iran, imposing an additional cost on the Islamic Republic for its current policies.

By all appearances, preventive action is neither "off the table" nor inevitable. A decision regarding preventive action will likely be influenced by a number of factors, including the outcome of ongoing diplomacy with Iran, the availability of detailed and accurate target intelligence, the impact of the war in Iraq on President George W. Bush's tolerance for risk, and the possibility that the president will avoid the snare of "paralysis by analysis" by basing a decision on a simple principle: that the overriding imperative of U.S. policy in the post-9/11 world is to keep the most dangerous weapons out of the hands of the most dangerous regimes. At any rate, should diplomacy fail, either of the remaining policy options available to Washington -- (a) preventive action or (b) deterrence and containment -- is likely to have immense consequences for the war on terrorism, the Middle East, and the role of the United States in the world.

Michael Eisenstadt is a senior fellow and director of the Military and Security Studies Program at The Washington Institute.