Part I: Is Iran Slowing its Nuclear Program?

Interview with Colin Kahl by Garrett Nada
Colin H. Kahl served as the deputy assistant secretary of defense for the Middle East from 2009 to 2011. He is currently an associate professor at Georgetown University’s School of Foreign Service and a senior fellow at the Center for a New American Security.

Iran has reportedly slowed down work on its nuclear program. What is actually known?
            The good news is that Tehran has kept its stockpile of 20 percent low-enriched uranium below the amount needed for a bomb. It may have curtailed uranium enrichment in order not to cross Israeli Prime Minister Benjamin Netanyahu’s red line. He had predicted in September 2012 that Iran would accumulate enough 20 percent low-enriched uranium for one bomb’s worth of material by the spring or summer of 2013. Netanyahu had implied that Israel would consider military action if Iran approached this point.
      Experts estimate that Iran would need about 551 pounds of 20 percent low-enriched uranium to produce a bomb. It reportedly has accumulated about 375 pounds so far, or two-thirds of the quantity needed. Iran could have had more, but it has oxidized part of the stockpile to make fuel plates for the Tehran Research Reactor. (Once oxidized, the uranium is not easily enriched to weapons-grade levels. It is technically reversible but time-consuming.)
      The bad news is that Iran has been significantly upgrading its ability to enrich uranium. It has installed about 2,000 additional IR-1 centrifuges at its enrichment facility in Natanz, bringing the total number of machines there to around 12,000, according to the U.N. nuclear watchdog in February. The installation of 200 even more advanced IR-2M centrifuges―which would be three to five times more efficient than IR-1 centrifuges―is particularly worrisome. And Iran intends to install about 3,000 of the more advanced models, which could dramatically shorten Iran’s breakout timeline.
            The Iranians may have run into some technical issue with storage or something else that requires them to oxidize part of their uranium stockpile. Another possibility is that Iran’s leaders want to avoid a major international crisis before the June 2013 presidential election. Or they could be intentionally skirting Netanyahu’s red line on the uranium stockpile to ensure Israel does not strike.
Has diplomacy with the international community played a role in Iran’s calculations?
            Tehran is likely to continue its dialogue with the world’s six major powers until its presidential election in June. But it is unlikely to make a major concession before the election for fear of signaling that the regime is weak.
            Supreme Leader Ayatollah Ali Khamenei ultimately decides on all nuclear issues. So the winner of the presidential election is not all that important per se. Most Iran analysts expect the next president to be handpicked by the supreme leader from the group loyal to him.
            After the election, the question will be whether Iran is willing to slow down its production of 20 percent low-enriched uranium and shift some of its stockpile abroad in exchange for some sanctions relief. That kind of deal is unlikely to solve the nuclear standoff. But it would put some time back on the clock.
            The United States, Britain, China, France, Germany and Russia, the so-called P5+1, are scheduled to meet with Iran in Kazakhstan again on April 5. During these talks, Tehran may try to weaken consensus among the world’s six major powers, who do not agree on every element of negotiating strategy. But this element of Iran’s diplomatic strategy has only had moderate success so far.
At what point would the United States need to decide whether or not to use force to stop the nuclear program?
            The Obama administration has indicated that it does not share Netanyahu’s definition of the red line for using force. Washington does not appear to consider one bomb’s worth of 20 percent low-enriched uranium alone as casus belli for a military strike. Even aggressive estimates claim Iran would need at least a month to convert further enrich this material to weapons-grade level (uranium enriched above the 90 percent level of purity). Iran would also have to do the enrichment at either Natanz or its second enrichment facility at Fordo, both of which are inspected every week or two by the U.N. nuclear watchdog. Inspectors would almost certainly catch Tehran diverting or enriching the material. Iran knows it would get caught, so the supreme leader is not likely to make such a move even with a sufficient stockpile of 20 percent low-enriched uranium.
            But President Obama and Prime Minister Netanyahu agreed in March that Iran would need at least one year to produce a nuclear device, which would begin with production of weapons-grade uranium. Tehran would then need several months to actually assemble a crude nuclear device. U.S. officials have suggested that Iran might need another two to four more years to build a nuclear device sophisticated enough to put on the tip of a ballistic missile.

            Obama administration officials, from the president on down, have consistently stated they will not allow Iran to acquire a nuclear weapon. And the president has made clear that all options, including the use of force, remain on the table to ensure that Iran does not get the bomb. At the same time, Obama clearly prefers a diplomatic solution, believing there is still time to strike a deal. All eyes will be on Almaty to see if the Iranians feel the same way.

Photo Credit: President Mahmoud Ahmadinejad via

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