AAAS Briefings: Iran May Be Struggling with Nuclear Technology and Technique

Iran is two to eight years away from being able to assemble a military nuclear explosive, according to two nuclear energy experts speaking at briefings sponsored by AAAS.

Speaking at the Rayburn House Office Building and later at AAAS headquarters, James Acton of King's College London and Jeffrey Lewis of the New America Foundation evaluated Iran's potential to build a nuclear weapon and discussed the effectiveness of international efforts to rein in its bomb-building ambitions. The briefings were sponsored by the AAAS's Center for Science, Technology and Security Policy.

Acton, who said he was expressing his own views, said that in a "worst case" it would take Iran at least until 2009, and probably longer, to acquire the enriched uranium needed to make a nuclear explosive.

"Although the evidence that Iran is looking to go into nuclear weapons is strong, none of the facilities that we know about are being used to manufacture nuclear weapons at the moment," said Acton.

Even if Iran acquired enough fissile material to fuel a bomb, the country may not have perfected the technical skill to actually make a nuclear explosive, he said.

"The engineering of a weapon is very difficult," said Acton. An atomic bomb requires precisely shaped and timed explosives that will compress the fissile materials enough to start a chain reaction.

Nations that have built the A-bomb, said Acton, "have found that the engineering challenge is bigger than they had thought" and took longer to accomplish than expected.

Lewis, director of the Nuclear Strategy and Nonproliferation Initiative at the New America Foundation and a member of the editorial advisory board of the Bulletin of the Atomic Scientists, said the last publicly available U.S. intelligence estimate is that Iran could not produce an atomic weapon before 2010 to 2015.

Lewis said that Iran is known to have about 3,000 centrifuges used to enrich uranium to weapon quality, but there is uncertainty about how efficiently atomic workers in Iran can operate the equipment.

"It seems to me that Iran is having trouble operating its centrifuges," said Lewis.

Lewis said that American political discussion about Iran focuses on prohibiting certain nuclear activities, but he argues that it is just as important to establish monitoring and safeguards within Iran "that would allow the intelligence community to have a better eye about what is going on."

For instance, Lewis said that if Iran agreed to disassemble its centrifuges, but would not permit additional monitoring, then the international community "would have a very difficult time" verifying that all of the centrifuge enrichment activity was, in fact, halted.

Alternatively, said Lewis, if Iran is allowed to operate the centrifuges with only some monitoring, then he believes "there is very little capacity in that case to guard against clandestine programs." This he called the "status quo" case.

Lewis said what is most needed is enhanced monitoring in Iran, inspections that match or exceed the so-called "best practices" used in other nuclear countries. Such inspection protocols, he said, would provide warning if Iran begins making a military nuclear weapon. But, in return for the enhanced monitoring, he said. Iran would probably expect to be permitted to do more nuclear work. "It seems very unlikely that we would get simultaneously more monitoring and less Iranian work," he said.

"If I am a policy-maker and I am looking at putting in place some kind of arrangement, I would be much more worried about the warning problem and getting timely intelligence than I am the things Iran is working on," he said.

Iran is a signatory to an international nuclear non-proliferation treaty. Compliance with the safeguard elements of the treaty in all of the signatory nations is monitored by the International Atomic Energy Agency.

In 2002, it was discovered by another group that Iran was building two secret nuclear facilities—a centrifuge plant and a heavy water reactor. That prompted international concern that Iran was building a bomb.

"These activities, had they been properly declared, would have been legal," said Lewis. "It was the manner in which Iran conducted the activities, not the activities themselves, that were a violation of the safeguard agreement."

The possibility of a nation conducting clandestine uranium became a concern in 1991 when it was discovered that Iraq was operating secret enrichment facilities. That prompted the IAEA to adopt a new, more intensive monitoring protocol.

Adopting the new protocols is voluntary by the treaty nations. Iran allowed the new protocol for a time, but then stopped it.

But even if Iran had accepted the additional protocols, Acton said, there is a strong possibility that a secret enrichment facility could escape the attention of the IAEA.

Detecting small centrifuge enrichment plants "is a very, very big challenge," he said. "Their environmental emissions are very small. They are almost undetectable from more than 10 to 20 kilometers away."

He said they are unlikely to be detected by aerial or orbital surveillance.

Acton said the IAEA has the authority, under the treaty, to seek out undeclared enrichment facilities, but "the technology for detecting secret plants is still at an early stage. There is still a lot more research work that needs to be done in this area."

Another way that a nation could secretly acquire enough enriched uranium to build a bomb, said Acton, is to divert it from a legal, declared nuclear facility.

"The IAEA safeguards are pretty good at detecting diversion," he said. "The amount of material, according to our calculations, that Iran could divert without being detected is much smaller than the amount that would be required for a nuclear bomb."

Acton said the concern is how quickly the IAEA would be able to detect a diversion of enriched uranium from the inventory of a declared plant. The IAEA now hopes that inventory monitoring would uncover such a diversion in about a year, but Acton said the agency "probably couldn't meet that target in every circumstance."

The United Nations and some of its member nations are seeking to persuade Iran to accommodate improved nuclear safeguards. Acton said the current safeguards at Iranian facilities are not as thorough as those practiced at enrichment plants in other nuclear nations.

"From what we can see, Iran is doing the minimum for enrichment plants that it can and stay within the letter of the safeguard agreement and that doesn't coincide with the best practices elsewhere in the world," said Acton.

Acton is a lecturer at the Centre for Science and Security Studies at King's College London. He has published studies analyzing the Iranian nuclear program. Acton is an advisor to the government of Norway on the technical and political aspects of verification of nuclear disarmament. He holds a Ph.D. in theoretical physics from the Cavendish Laboratory, Cambridge.

Lewis's organization, the Nuclear Strategy and Nonproliferation Initiative, seeks to reduce the role of nuclear weapons in international security and to strengthen controls in the Nuclear Non-Proliferation Treaty. Lewis previously was executive director of the Managing the Atom Project at Harvard University's Belfer Center for Science and International Affairs. He maintains a blog on nuclear arms control and nonproliferation called ArmsControlWonk.com. Lewis holds a Ph.D. in international security and economic policy from the University of Maryland.

Paul Recer

19 November 2007