In my article “Not Time to Attack Iran” (March/April 2012), I made the case for pursuing a diplomatic solution to the Iranian nuclear challenge, arguing that, because of the risks and costs associated with military action, “force is, and should remain, a last resort, not a first choice.” Key developments in 2013 -- namely, the election of Hassan Rouhani, a moderate, as Iran’s new president and the signing of an interim nuclear deal by Iran and the United States and its negotiating partners -- reinforce this conclusion. Whatever hawks such as Reuel Marc Gerecht or Matthew Kroenig might argue, it is still not time to attack Iran. Indeed, the prospects for reaching a comprehensive agreement to resolve the nuclear impasse peacefully, while far from guaranteed, have never been brighter. 


After decades of isolation, the Iranian regime may finally be willing to place meaningful limits on its nuclear program in exchange for relief from punishing economic sanctions. In Iran’s June 2013 presidential election, Rouhani handily defeated a slate of conservative opponents, including the hard-line nuclear negotiator Saeed Jalili, who had campaigned on continuing Iran’s strategy of “nuclear resistance.” Rouhani, in contrast, pledged to reach a nuclear accommodation with the West and free Iran from the economic burden imposed by sanctions. Rouhani, also a former nuclear negotiator, believes he has the support of the Iranian people and a green light from Supreme Leader Ayatollah Ali Khamenei to reach a comprehensive nuclear accord with the United States and the other members of the P5+1 (Britain, China, France, Germany, and Russia).

The first step on the road to a comprehensive deal came in November 2013 with an interim agreement in Geneva, in which Tehran agreed to freeze and modestly roll back its nuclear program in exchange for a pause in new international sanctions and a suspension of some existing penalties. The deal represents the most meaningful move toward a denuclearized Iran in more than a decade. It neutralizes Iran’s stockpile of 20 percent uranium and therefore modestly lengthens Iran’s “breakout” timeline -- the time required to enrich uranium to weapons grade -- by one or two months. A new inspections regime also means any breakout attempt would be detected soon enough for the international community to react, and expanded International Atomic Energy Agency (IAEA) access to Iran’s nuclear infrastructure will make it more difficult for Iran to divert critical technology and materials to new secret sites. The terms also preclude the new plutonium reactor at Arak from becoming operational, halting the risk that Iran could soon use plutonium to build a bomb.

For all its good points, the interim agreement does not by itself resolve the Iranian nuclear challenge. Rather, the accord is designed to create at least a six-month diplomatic window (the initial period of the agreement), or longer if the agreement is extended, to negotiate a final, comprehensive solution. At the very least, U.S. officials have suggested that the ultimate deal must permanently cap Iran’s enrichment at five percent; substantially reduce Iran’s low-enriched uranium stockpile; place significant limits on the number of Iranian centrifuges and enrichment facilities; dismantle Arak or convert it to a proliferation-resistant light-water reactor; allow much more intrusive inspections of both declared and undeclared facilities; and account for the “past military dimensions” of Iran’s nuclear research. In exchange, Iran would receive comprehensive relief from multilateral and national nuclear- and proliferation-related sanctions.


Some analysts argue that U.S. negotiators should use the leverage created by crippling economic sanctions and Iran’s apparent willingness to negotiate to insist on a total dismantling of Iran’s fuel-cycle activities. The maximalist approach is reflected in Israeli Prime Minister Benjamin Netanyahu’s stated requirements for a final deal: no uranium enrichment at any level, no stockpile of enriched uranium, no centrifuges or centrifuge facilities, and no Arak heavy-water reactor or plutonium reprocessing facilities.

Attempting to keep Iran as far away from nuclear weapons as possible seems prudent and reasonable. It is imperative that any final deal prohibits Iran from possessing facilities that would allow it to produce weapons-grade plutonium, for example. But in reality, the quest for an optimal deal that requires a permanent end to Iranian enrichment at any level would likely doom diplomacy, making the far worse outcomes of unconstrained nuclearization or a military showdown over Tehran's nuclear program much more probable. Regardless of pressure from the United States, its allies, and the wider international community, the Iranian regime is unlikely to agree to end all enrichment permanently.

Khamenei, the ultimate decider on the nuclear file, has invested far too much political capital and money (more than $100 billion over the years) in mastering enrichment technology and defending Iran's nuclear rights (defined as domestic enrichment). The nuclear program and “resistance to arrogant powers” are firmly imbedded in the regime’s ideological raison d’être. So, even in the face of withering economic sanctions, Khamenei and hard-liners within the Revolutionary Guard are unlikely to sustain support for further negotiations -- let alone acquiesce to a final nuclear deal -- if the end result reflects a total surrender for the regime. As Alireza Nader, an Iran analyst at the RAND Corporation, observes, “[S]anctions are a danger to their rule, but weakness in the face of pressure might be no less a threat.”

Nor are Rouhani and his negotiating team likely to agree to halt enrichment or advocate for such a policy, since doing so would be political suicide. In 2003, during Rouhani’s previous role as Iran's chief nuclear negotiator, he convinced Khamenei to accept a temporary suspension of enrichment. But further talks with the international community stalled in early 2005 over a failure to agree on Iran’s asserted right to enrichment, and Tehran ended its suspension shortly thereafter. Rouhani is unlikely to let that happen again. 


Given the certainty that Iran will reject maximalist demands from the United States, the United States should only make such demands if it is willing to go to the brink of the abyss with Iran, escalating economic and military threats to the point at which the regime’s survival is acutely and imminently in danger. Yet pursuing such a high-risk strategy is unlikely to succeed, and the consequences of failure would be profound.

First, it is unclear whether any escalation of sanctions could bring the regime to its knees in time to prevent Iran from achieving a breakout capability. Iran’s apparent willingness to negotiate under pressure is not, in and of itself, evidence that more pressure will produce total surrender. Iran’s economy is in dire straits, but the country does not appear to be facing imminent economic collapse. Khamenei and the Revolutionary Guard also seem to believe that the Islamic Republic weathered far worse during the Iran-Iraq War, an eight-year conflict that killed hundreds of thousands of Iranians and produced over half a trillion dollars in economic losses before Iran agreed to a cease-fire. Even if Washington goes forward with additional sanctions, economic conditions are not likely to produce enough existential angst among Iranian leaders, generate mass unrest, or otherwise implode the regime before Iran achieves a nuclear breakout capability. And even if they did lead to regime change, it still might not prove sufficient to force a nuclear surrender. After all, the imprisoned leaders of the Green Movement and Iranian secularists opposed to the Islamic Republic, as well as a significant majority of the Iranian people, also support Iran’s declared right to enrichment.

Second, and somewhat paradoxically, ramping up sanctions to force regime capitulation now could end up weakening international pressure on Iran. For better or worse, Rouhani has already succeeded in shifting international perceptions of Iran. If the United States, rather than Iran, comes across as intransigent, it will become much more difficult to maintain the international coalition currently isolating Tehran, particularly on the parts of China, Russia, and numerous other European and Asian nations. Some fence sitters in Europe and Asia will start to flirt with Iran again, leaving the United States in the untenable position of choosing between imposing extraterritorial sanctions on banks and companies in China, India, Japan, South Korea, Turkey, and elsewhere, or acquiescing to the erosion of the international sanctions architecture.

Third, issuing more explicit military threats (through public warning by U.S. President Barack Obama or congressional passage of a resolution authorizing the use of military force, for example) is also unlikely to achieve a maximalist diplomatic outcome. There is little doubt that maintaining a credible military option affects the Iranian regime’s calculations, raising the potential costs associated with nuclearization. And if diplomacy fails, the United States should reserve the option of using force as a last resort. But threats to strike Iranian nuclear sites surgically, no matter how credible, would not create a sufficient threat to the survival of the regime to compel it to dismantle its nuclear program completely.

Finally, attempting to generate an existential crisis for the Islamic Republic could backfire by increasing the regime’s incentives to acquire nuclear weapons. If the United States escalates economic or military pressure at the very moment when Iran has finally begun to negotiate in earnest, Khamenei will likely conclude that the real and irrevocable goal of U.S. policy is regime change. Solidifying this perception would enhance, rather than lessen, Tehran’s motivation to develop a nuclear deterrent. In short, playing chicken with Iran will not work and is likely to result in a dangerous crash. Gambling everything by insisting on an optimal deal could result in no deal at all, leaving Iran freer and potentially more motivated to build atomic arms and making a military confrontation more likely.


During a December 2013 forum hosted by the Brookings Institution, Obama said, “It is in America’s national security interests . . . to prevent Iran from getting a nuclear weapon. . . . But what I’ve consistently said is, even as I don’t take any options off the table, what we do have to test is the possibility that we can resolve this issue diplomatically.” When asked by a former Israeli general in the audience what he would do if diplomacy with Iran breaks down, Obama said, “The options that I’ve made clear I can avail myself of, including a military option, is one that we would consider and prepare for.”

Given the dangers associated with a nuclear-armed Iran, Obama is right to keep the military option alive. But he is also right to strongly prefer a diplomatic outcome. Leadership changes in Tehran and the diplomatic momentum created by the Geneva interim accord mean that there is a real chance that the Iranian nuclear crisis -- a challenge that has haunted the international community for decades -- could finally be resolved peacefully. No one can say for sure how high the odds of success are. But given the enormous dangers associated with both an Iranian bomb and the bombing of Iran, it is imperative to give diplomacy every chance to succeed.

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  • COLIN H. KAHL is an associate professor in the Security Studies Program in the Edmund A. Walsh School of Foreign Service at Georgetown University.
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