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On November 8, 2011, the Board of Governors (BoG) of the International Atomic Energy Agency (IAEA) released a highly-anticipated report on Iran's nuclear programme . While the IAEA's BoG produces several reports on Iran every year which consistently find Tehran to be lacking in terms of its safeguards obligations under the Non-Proliferation Treaty (NPT), the most recent report was particularly significant in that it contained unprecedented detail on Iranian activities that could be relevant to development of a nuclear weapon. Its publication has increased concerns as to the true nature of Iran's nuclear programme and has provoked a strong response from the international community. On November 18 the IAEA BoG adopted a resolution in which it expressed "deep and increasing concern about the unresolved issues regarding the Iranian nuclear programme" . On November 21, the United States reacted by adopting new sanctions aimed at Iran's petrochemical, energy and financial sectors . The European Union, currently the destination for one-fifth of Iran's petrochemical exports, followed suit with an "unprecedented" oil embargo in January 2012, a move that has potentially damaging consequences for Iranian oil revenues .
In the international press the BoG report has been widely interpreted as confirmation that Iran is intent on acquiring a nuclear weapon and is close to fulfilling this goal. Some analysts now argue that the benefits of a pre-emptive strike against Iran's nuclear facilities now outweigh the costs . Israel, the country perceived by many as most likely to carry out such an attack, remains determined to prevent Iran from "turning nuclear" . Iran, by contrast, has been consistent in its claim that its nuclear programme is peaceful and for the purposes of energy production. Iranian officials described the BoG report as "unbalanced" and "politically motivated" . In this context, Tehran has responded defiantly to new and increased sanctions by repeatedly threatening to close the Strait of Hormuz, through which passes 20 percent of the world's oil. Iran's rhetoric has in turn prompted the US, the UK and France to increase their military presence in the area . International tensions will likely escalate further in the coming months.
In this article I examine the key technical issues surrounding Iran's nuclear programme and the significance of the November 8 BoG report.
At the core of all nuclear weapons is fissile material, either highly enriched uranium (HEU) or plutonium (Pu) . These materials do not occur naturally in significant quantities and must be produced, either through the enrichment of uranium or its irradiation in a nuclear reactor to produce plutonium. The acquisition of fissile material is seen as the key hurdle in the development of nuclear weapons although the construction of a nuclear warhead is also a complex task for which specific research and development work, collectively referred to as weaponization, must be carried out and coordinated with the development of a delivery system. However, a nuclear weapons programme cannot be definitively inferred from progress in these areas. Fissile material is used in nuclear power reactors; experiments relevant to weaponization can have civil or other military applications; and delivery systems such as ballistic missiles are also used to deliver conventional payloads. Given the dual uses of these materials and technologies it is possible for a state to develop an indigenous technical capacity ostensibly for civil nuclear purposes but with the option to produce nuclear weapons in a short time frame, which may range from several weeks to a couple years . This is a strategy commonly referred to as "nuclear hedging" which can leave a state within months or years of having nuclear weapons while maintaining its non nuclear weapon state (NNWS) status under the NPT. Nuclear hedging has in the past been used to describe the programmes of highly industrialised countries such as Japan, South Korea and Germany before increased transparency in their nuclear development and greater international oversight through implementation of measures, such as the Additional Protocol for the application of safeguards, served to allay international concerns.
Iran's low-enriched uranium stockpile
Iran has steadily expanded its uranium enrichment programme since the introduction of uranium hexafluoride to its Fuel Enrichment Plant at Natanz in February 2007. According to the most recent BoG report released in February 2012, this facility has been used to produce just less than 5,500 kg of 3-5% low enriched uranium (LEU), with approximately 100 kg of 19.75% LEU produced at the adjacent Pilot Fuel Enrichment Plant (PFEP). To put these percentages in perspective, bomb-grade material is considered to be 90% U-235. In December 2011 uranium enrichment was started at a second site, the Fordow Fuel Enrichment Plant (FFEP) near the city of Qom, and just over 10 kg of 19.75% LEU has been produced as of February 2012. Enrichment to date has utilized the relatively inefficient Ir-1 centrifuge, which is based on 1970's gas centrifuge technology, with approximately 9,000 currently installed at Natanz. Iranian scientists are also carrying out research and development on more advanced designs, the Ir-2m and the Ir-4, which use carbon fibre rotors (as opposed to high strength aluminium) and would likely have separative capacities many times greater than the Ir-1. In mid-February 2012 Iran announced ‘huge' nuclear progress with the production of a 4th generation centrifuge and plans to install three variants, the Ir-5, Ir-6 and Ir-6s, at the PFEP. However, the very fact that Iran will now be conducting trials on three new centrifuge models alongside the Ir-2m and Ir-4 models implies that they are still some way from mastering advanced centrifuge technology and deploying a next generation centrifuge design.
Iran's enrichment programme is a source of continuing international concern due to its illicit procurement of technology, covert development, and the absence of a credible civil rationale. Tehran initially acquired gas centrifuge designs and components from the A.Q. Khan proliferation network in the 1980's, which provided similar technology for Libya's and North Korea's nuclear weapons programmes. The enrichment site at Natanz was first revealed to the international community by the National Council of Resistance of Iran (NCRI), an exiled opposition group, more than a decade after Iran began work on enrichment. This pattern of opaque nuclear development was repeated with the FFEP, which Tehran first reported to the IAEA in September 2009 just days before the US, UK and France presented clear evidence that it had been under construction for many years. Finally, while Iran's stated rationale for its nuclear programme is energy generation to meet future requirements, there are currently no nuclear power plants (NPP) in Iran where the LEU produced could be used. The Bushehr NPP uses Russian fuel while the NPP planned at Dvorkin is by optimistic estimates a decade away from completion.
Iran's growing stockpile of LEU is of particular concern to those worried about Iran's nuclear intentions because it provides a source of material that could be further enriched to a level suitable for use in nuclear weapons. While estimates vary as to how long this would take (from two to six months), it would certainly be much quicker than having to start from natural uranium . Consequently, recent diplomatic efforts have focused on reducing this stockpile, which is now sufficient to produce several nuclear weapons. In October 2009, for example, the IAEA proposed that Iran send a significant proportion of its stockpile to Russia and France for conversion into fuel for the Tehran Research Reactor. While this measure was agreed to in principle, implementations terms acceptable to all parties were not reached and the initiative collapsed in May 2010.
A parallel weaponization program?
As well as detailing Iran's enrichment and other fuel cycle activities, the BoG report contains a 14-page annex on possible military dimensions to Iran's nuclear programme. The Annex presents a record of procurement, research, development and testing activities stretching back many years. While the IAEA has been aware of this for some time and previous BoG reports have expressed concern at many of these activities the Agency has never before released such a comprehensive account. The report, described in the following paragraphs, strongly suggests that Iran has made significant progress in accomplishing most if not all of the technical steps necessary to produce and deliver an implosion-type nuclear weapon .
According to the report, in 1987 Iran acquired a document via the A.Q. Khan network which describes how to convert gaseous UF6 into uranium metal and produce hemispheres of enriched uranium (the shape and form necessary for use in a nuclear weapon). It is alleged that Iranian scientists have since performed experiments on the conversion of uranium compounds into metal. While Iran has admitted that it received the aforementioned document it claims that it was part of a package of information on centrifuge technology and that it "had not been requested" . The report also claims that Iran has performed research into the simultaneous detonation of high explosives and carried out at least one large scale test in 2003 to generate a converging shockwave. In a nuclear weapon such a system is used to compress the fissile core to a critical density capable of sustaining a nuclear chain reaction. Moreover, the BoG report claims that Iran has recently experimented with materials and components capable of producing bursts of neutrons, which are used in nuclear weapons to trigger the chain reaction. In support of these activities, hydrodynamic tests where fissile and nuclear materials are simulated by other materials for the purpose of design optimization are also reported to have been carried out through the early 2000s, while modelling studies on the shock compression of the HEU core of a nuclear weapon are said to have been carried out in 2008 and 2009. With regard to the delivery of a nuclear weapon it is alleged that between 2002 and 2003, Iran conducted engineering studies on how to integrate a spherical payload of suitable mass and dimensions for a nuclear warhead into the re-entry vehicle of its Shahab-3 missile. Research is also said to have been performed into the development of a firing system to enable this payload to explode at a height greater than 600 m above a target or upon impact with the ground. An airburst detonation at this height strongly implies a nuclear payload – the nuclear bomb dropped on Hiroshima in 1945 was exploded at a height of 580 meters.
The IAEA previously shared the bulk of this evidence with Iran in early 2008. Tehran responded in May of that year with a 117-page assessment which confirmed certain basic details (people, places and organizations), but dismissed all allegations of work towards nuclear weaponization, claiming that the information supporting these claims had been fabricated. The reliability of the information upon which the IAEA's assessment is based remains a key source of contention due to a significant portion being derived from covert intelligence supplied by member states. However, the IAEA has sought to address this issue in the BoG report by emphasising that intelligence was received from multiple member states and was consistent with other independent sources such as IAEA verification activities, interviews carried out with individuals involved in Iran's nuclear programme, satellite imagery, and grey literature.
Significance of the IAEA report
While the IAEA November report has been held up by some as proof that Iran has made the decision to acquire nuclear weapons and may do so imminently, it does not contain definitive conclusions as to the direction of Iran's nuclear programme or provide timelines. Furthermore, much of the information regarding Iranian activities set out in the report is not new; the report simply draws together and confirm information presented through other sources. For example, the report is broadly consistent with unclassified summary of the 2007 US National Intelligence Estimate, which concluded with high confidence that Iran's nuclear weapons programme was halted in 2003, while keeping open the possibility that Iran may continue with nuclear weapon relevant research. This said, the IAEA goes further in that the BoG report implies that weapons- relevant activities were restarted in 2006 or earlier, even if they were not part of a full scale nuclear weapons programme. In general terms, however, the IAEA report has reinforced pre-existing concerns rather than presenting damning revelations, with technical indicators implying that Tehran is moving slowly but steadily towards a nuclear hedging capability.
What is perhaps more interesting about the report is the fact that it demonstrates what appears to be a significant change in approach on the part of the IAEA. Past reports from the BoG have been characterized by their reluctance to court controversy and have presented the Iranian case in more abstract terms. Under the leadership of new Director General Yukiya Amano, however, the IAEA seems increasingly willing to pursue evidence on the military-relevant dimensions of Iran's programme. This development has important implications in terms of legitimizing the increasingly severe international measures aimed at halting, or even reversing, Iran's nuclear programme. A new round of talks between Iran and the P5+1 (US, UK, France, Russia, China and Germany), the first since January 2011, are expected to take place in Turkey in April 2012, although it is too early to tell whether recently increased pressure will be sufficient to force Iran into serious negotiations on its nuclear programme.
Over the past four and a half years Tehran has been the subject of four UN Security Council Resolutions and multiple rounds of sanctions, yet has continued to push steadily ahead with its nuclear development. Still, the most recent IAEA visit to Iran at the end of January 2012 was potentially significant in that it included two senior weapons specialists in the visiting delegation; in the past, delegations have not usually included inspectors with such experience and knowledge. This has led some analysts to believe that Iran may be prepared to begin meaningful discussions on the possible military aspects to its programme for the first time. However, this optimism must be tempered by Iran's refusal in late February to allow IAEA inspectors to visit the Parchin military site, south of Tehran, where Iranian scientists in the past are suspected of carrying out hydrodynamic tests in support of nuclear warhead design optimisation. In any case, with EU sanctions set to come into full effect in June and the negotiations between the West and Iran set to resume in April 2012, the BoG report has added a new dimension to the Iranian nuclear question.
1. "Board of Governors Report on the implementation of safeguards in Iran, IAEA", November 8, 2011.
2. "Implementation of the NPT safeguards agreement and relevant provisions of United Nations Security Council resolutions in the Islamic Republic of Iran Resolution adopted by the Board of Governors", IAEA, November 18, 2011.
3. "Executive Order 13590 -- Iran Sanctions", White House, November 21, 2011.
4. "PM, Chancellor Merkel and President Sarkozy statement on Iran sanctions", PM Office, January 23, 2012.
5. See, for example, the controversial New York Times article by Ronen Bergman: "Will Israel Attack Iran?," New York Times, January 25, 2012; Matthew Kroenig, "Time to attack Iran: Why a strike is the least bad option," Foreign Affairs, January/February 2012.
6. Greg Thielmann and Benjamin Loehrke, "Chain reaction: How the media has misread the IAEA's report on Iran," Bulletin of the Atomic Scientists, November 23, 2011; "If Iran gets the bomb", Wall Street Journal, November 14, 2011.
7. Mitra Amiri, "Iran says sanctions to fail, repeats Hormuz threat", Reuters, January 25, 2012.
8. David Blair, "Britain, US and France send warships through Strait of Hormuz", The Telegraph, January 23, 2012.
9. Natural uranium contains 0.7% of the fissile isotope 235U. For the purposes of power generation this is typically increased to 3-5% for use in light water nuclear reactors in a process known as uranium enrichment. Highly enriched uranium (HEU) has a concentration of 235U of 20% or more, although material used in nuclear weapons typically has an enrichment level greater than 90% and is referred to as "weapons grade".
10. Ariel E. Levite, "Never say never again: nuclear reversal revisited", International Security 27: 3, Winter 2002–2003, p. 69.
11. David Albright and Christina Walrond, "Debunking Gregory Jones Again", Institute for Science and International Security, October 27, 2011.
12. There are two basic nuclear weapon designs suitable for use with HEU, a basic "gun-type" design (similar to the "Little Boy" nuclear weapon dropped on Hiroshima in 1945) and the more sophisticated "implosion-type" design.
13. Implementation of the NPT Safeguards Agreement and relevant provisions of Security Council resolutions 1737 (2006), 1747 (2007) and 1803 (2008) in the Islamic Republic of Iran, p. 5, IAEA, <http:// www.iaea.org/Publications/Documents/Board/2008/gov2008-38.pdf>, September 15, 2008.
Centre for Science and Security Studies,
Department of War Studies
King's College London
Christopher Hobbs is an early-career Leverhulme Research Fellow working in the Department of War Studies at King's College London University, UK. A physicist by training, he has carried out research on nuclear non-proliferation, nuclear terrorism and more specifically how the Department of Safeguards at the IAEA can more efficiently utilise open source information.