Key Questions

  • Does Iran want nuclear weapons?
  • Should Iran decide to get a nuclear weapon, how long would it take to acquire the bomb?
  • Where does Iran stand on the road to a nuclear bomb?
  • How does that compare to where Iran stood a decade ago?
  • How has the U.S. attempted to prevent Iran from acquiring a nuclear bomb?
  • How could Iran get the bomb?
  • What could be the consequences of a nuclear-armed Iran?
  • If diplomacy fails, how could the United States respond to the Iranian nuclear challenge?

. . . 

Does Iran want nuclear weapons?

Yes and no. 

On the one hand, Iran already mastered the technologies to indigenously enrich uranium in 2008 and has the capability with its own know-how and resources to build a bomb if it chooses to do so. While Iran justifies its extensive nuclear program on the basis of meeting its own electricity needs, the country already maintains a contract with Russia, good for 10 years, to provide sufficient fuel for its single operating nuclear reactor at Bushehr. The discovery of two previously covert enrichment facilities at Natanz and Fordow (the latter dug deep underground, sheltered from foreign surveillance or attack) by Western intelligence agencies has invited greater suspicion. Additionally, a 2007 National Intelligence Estimate assessed “with high confidence that until fall 2003, Iranian military entities were working under government direction to develop nuclear weapons.” The extent and current status of Iran’s “weaponization” activities, past and present, remains shrouded in mystery. 

Finally, Iran is surrounded by mostly hostile nations and has a deeply adversarial relationship with Israel and the United States, giving it plenty of reasons to want to develop nuclear weapons. More recently, recent Western intervention in the Middle East has provided evidence for those who argue that nuclear weapons offer protection from attack. As former Undersecretary of Defense Eric Edelman put it, if you are like Iraq and do not have nuclear weapons, you get invaded; if you are like Libya and give up your nuclear program (as Colonel Qaddafi in 2003), you only get bombed. In March 2011, as the NATO intervention in Libya began, Iran’s Supreme Leader Ali Khamenei noted that Qaddafi “wrapped up all his nuclear facilities, packed them on a ship and delivered them to the West. . . . Look where we are, and in what position they are now.” 

On the other hand, Iranian leaders have made a variety of statements disavowing nuclear weapons. Supreme Leader Ali Khamenei has reportedly issued a fatwa against the use or development of atomic weapons, and President Hassan Rouhani told NBC News in September 2013: “We have time and again said that under no circumstances would we seek any weapons of mass destruction including nuclear weapons, nor will we ever.” There is no direct evidence that Iran has made a decision to acquire a nuclear weapon, and there is reason to believe that if Iran wanted a nuclear bomb, it would have produced one by now. 

Bottom line: there is no evidence that Iran has made a decision to acquire a bomb, but it seems clear that it wants the option to do so. 

Should Iran decide to get a nuclear weapon, how long would it take to acquire the bomb?

At least a year, in the judgment of the U.S. intelligence community, and even longer in the view of many experts and the intelligence communities of other nations. The time required to implement a decision to get a bomb is a function of a number of technical factors, including: (1) the size of Iran’s stockpiles of low- and medium-enriched uranium; (2) the number and efficiency of centrifuges it is using to enrich uranium; and (3) the capabilities and competencies Iran has developed for using high-enriched uranium to build a testable bomb. 

Where does Iran stand on the road to a nuclear bomb?

As Harvard professor and Belfer Center director Graham Allison puts it, “Iran has overcome the most significant obstacle to making a bomb: it has mastered the technologies to enrich uranium indigenously. It has operated production lines to produce a stockpile of low enriched uranium (LEU) that, after further enrichment, would provide the cores for more than six nuclear bombs. Since 2010 it has been enriching uranium to a level of 20 percent (medium enriched uranium or MEU). As a technical fact, that means it has done 90 percent of the work required to produce the highly enriched uranium (HEU) needed for an explodable nuclear bomb.”


To use the metaphor of American football, enriching to 5% (LEU) is equivalent to marching 70 yards down the field to our 30 yard line. Enriching to 20% drives into the red zone, down to the 10-yard line, completing nine-tenths of the work to make the material for a bomb.


According to today’s estimates, Iran has produced sufficient uranium, after further enrichment, for 7-8 nuclear bombs.

How does that compare to where Iran stood a decade ago?

As Secretary of State John Kerry himself noted, in 2003, Iran had only 164 centrifuges and was many years away from a bomb. Since then, the U.S., EU, UN, and others imposed sanctions that have squeezed Iran’s economy, while nonetheless allowing Iran’s nuclear program to advance, shortening the timeline from decision to bomb. 

For more on Iran’s slow march closer and closer to the bomb, see the Council on Foreign Relations’ interactive Crisis Guide

How has the U.S. attempted to prevent Iran from acquiring a nuclear bomb?

For the past decade, the principal strategy followed by the U.S. government under both Republican and Democratic administrations has been to declare demands: Iran must not do A; Iran will not be permitted to do B (after Iran has done A); Iran cannot do Z. . . . In addition, the U.S. has led an effort to impose economic pain on Iran through sanctions. Initially, these were largely symbolic. In the past two years, however, the U.S. and key allies have begun taking actions that are actually biting. If one believes what one reads in the papers, the program of sanctions has been complemented by a series of covert actions including cyberwar or cyber-sabotage that included Stuxnet, Duqu, and Flame, assassinations of key scientists in the Iranian nuclear program, and unnatural explosions at key Iranian missile and steel plants.* 

*Borrowed from Graham Allison, “Will Iran Get a Bomb—or Be Bombed Itself—This Year?” (Atlantic, 8/1/13)


How could Iran get the bomb?

While analysts overwhelmingly focus on “breakout”—the time needed for Iran to produce enough HEU, using declared facilities, without inviting attack—Iran’s two other options are arguably more likely: “sneak out” and “buy.” By diverting and enriching uranium to 90 percent at a covert enrichment plant, the sneak out option could allow Iran to produce sufficient material for a bomb without being detected. Alternatively, Iran could buy enough material, or even a ready-made bomb, from a willing seller abroad. As former Secretary of Defense Robert Gates famously said, North Korea will “sell anything they have to anybody who has the cash to buy it.” Kim Jong-il sold Syria a nuclear reactor that by now would have produced enough plutonium for Syria’s first bomb, had it not been destroyed by an Israeli airstrike in 2007.


What could be the consequences of a nuclear-armed Iran?

Many expect Iran’s acquisition of nuclear weapons would give way to what a UN panel described in 2004 as a “cascade of proliferation” across the Middle East. After that report, Graham Allison predicted that “If Iran goes nuclear, Egypt will follow, then Saudi Arabia (more likely buying than making).” King Abdullah told U.S. Special Envoy Dennis Ross as much in 2009 (“we will get nuclear weapons”), and many felt such concerns were validated by a recent BBC report that Saudi Arabia “believes it could obtain atomic weapons at will” from Pakistan. Paul Bracken, among others, argues nuclear weapons would provide a shield under which Iran would be able to expand international terrorism operations. Finally, in his book Nuclear Terrorism, Allison raised the possibility of Iran providing nuclear weapons to the terrorist group Hezbollah.

If diplomacy fails, how could the United States respond to the Iranian nuclear challenge?




Stricter sanctions, sabotage, and other pressure

Roger Cohen (11/14/11): “What is needed is a contain-and-constrain policy. Contain Iran through beefed-up Israeli and Gulf defenses, a process underway. Constrain it to circle in its current nuclear ambiguity through covert undermining (Stuxnet 2.0, etc.), tough measures to block its access to hard currency, and, as a last resort, a ‘quarantine’ similar to John Kennedy’s interdiction of shipping to Cuba during the missile crisis.”

Robert Einhorn (10/14/13): “Generating international support for ratcheting up sanctions will be very difficult – especially if we are seen to be de-emphasizing a diplomatic solution and the Iranians are seen finally to be willing to accept significant constraints on their nuclear program.”

Military strike against Iran’s nuclear facilities

Matthew Kroenig (1/24/12): “A US strike would cause immense damage to Iran’s nuclear program. It is unlikely that Iran has significant operational nuclear facilities that America doesn’t know about. The United States could destroy Iran’s known facilities.”

Amos Yadlin (11/4/13): “I still believe that if President Obama has to choose between Iran becoming nuclear and a military attack —  he will choose a military attack…My argument when I speak to my American friends is, ‘Don’t go to war! Go for a one-night operation. You can do it.”

Robert Einhorn (10/24/13): “The military option could trigger an Iranian decision to kick out inspectors, withdraw from the NPT, and move as quickly as possible to build nuclear weapons. It could give Iranian advocates of early nuclear weaponization something they’ve wanted for years – a green light to cross the nuclear threshold.” Also, “an attack would almost surely precipitate the demise of international sanctions efforts.”

Kenneth Pollack (9/22/13): “Even after a devastating American military strike, I fear the Iranians would pick themselves up and rebuild — and would withdraw from the NPT, evict any remaining nuclear inspectors and deploy an actual arsenal to deter a future American strike.”

Regime change

 Jamie Fly and Gary Schmitt (1/17/12): “If the United States seriously considers military action, it would be better to plan an operation that not only strikes the nuclear program but aims to destabilize the regime, potentially resolving the Iranian nuclear crisis once and for all.”

Robert Einhorn (10/24/13): “Despite widespread discontent inside Iran, the Islamic Republic has proven to be very resilient. Cycles of relative moderation following periods of conservative orthodoxy have provided a kind of safety valve for the regime.”


Paul Pillar (11/19/13): “Iran has evolved significantly even during the three decades of the Islamic Republic...most of it has been in directions that entail improvement from our point of view…More, rather than less, normal interaction with the Iranians is what will not just continue but accelerate these trends, leading to effects such as those Khouri describes.  This is the way to encourage political and social change in Iran.”

John Bolton (9/29/13): “Mr. Rouhani's strategy is clear: Lower the rhetorical temperature about the nuclear issue; make temporary, cosmetic concessions, such as allowing inspections by the International Atomic Energy Agency at already-declared nuclear sites; and gain Western acceptance of its "reactor-grade" uranium enrichment. Once that goal is attained, Iran's path to nuclear weapons will be unobstructed and within Tehran's discretion.”


Kenneth Pollack (10/22/13): “Containment is hardly a perfect policy, but I see the costs and risks as more easily mitigated than those of war…Properly understood, containment would put pressure on Iran in various ways, to keep it on the defensive and to encourage the end of the regime. It would hold in place painful sanctions. It would include covert assistance to the Iranian opposition, cyberwarfare in response to Iran’s support for terrorism, and continued diplomatic isolation.”

Kenneth Waltz (July/August 2012): “By reducing imbalances in military power, new nuclear states generally produce more regional and international stability, not less.  Israel's regional nuclear monopoly, which has proved remarkably durable for the past four decades, has long fueled instability in the Middle East. In no other region of the world does a lone, unchecked nuclear state exist. It is Israel's nuclear arsenal, not Iran's desire for one, that has contributed most to the current crisis. Power, after all, begs to be balanced.”

Colin Kahl, Raj Pattani, and Jacob Stokes (May 2013): “Containment on the cheap might suffice to counter the least likely dangers emanating from a nuclear-armed Iran – intentional Iranian nuclear use against the United States – but would probably fail to address the more likely dangers associated with a volatile, crisis-prone Middle East.”