By DAVID E. SANGER and WILLIAM J. BROAD
The New York Times, 8 Nov 2011 – United Nations weapons inspectors have amassed a trove of new evidence that they say makes a “credible” case that “Iran has carried out activities relevant to the development of a nuclear device,” and that the project may still be under way.
The long-awaited report, released by the International Atomic Energy Agency on Tuesday, represents the strongest judgment the agency has issued in its decade-long struggle to pierce the secrecy surrounding the Iranian program. The findings, drawn from evidence of far greater scope and depth than the agency has previously made public, have already rekindled a debate among the Western allies and Israel about whether increased diplomatic pressure, sanctions, sabotage or military action could stop Iran’s program.
Knowing that their findings would be compared with the flawed Iraq intelligence that preceded the 2003 invasion — and has complicated American moves on Iran — the inspectors devoted a section of the report to “credibility of information.” The information was from more than 10 countries and from independent sources, they said; some was backed up by interviews with foreigners who had helped Iran.
The report laid out the case that Iran had moved far beyond the blackboard to create computer models of nuclear explosions in 2008 and 2009 and conducted experiments on nuclear triggers. It said the simulations focused on how shock waves from conventional explosives could compress the spherical fuel at the core of a nuclear device, which starts the chain reaction that ends in nuclear explosion.
The report also said Iran went beyond such theoretical studies to build a large containment vessel at its Parchin military base, starting in 2000, for testing the feasibility of such explosive compression. It called such tests “strong indicators of possible weapon development.”
The inspectors agreed with a much-debated classified United States National Intelligence Estimate issued in 2007 that Iran had dismantled a highly focused effort to build a bomb in late 2003, but found significant recent work, though conducted in a less coordinated manner.
The report does not claim that Iran has mastered all the necessary technologies, or estimate how long it would take for Iran to be able to produce a nuclear weapon. Inspectors do not point to a single weapons lab, or provide evidence of a fully constructed nuclear weapon. Instead, the report describes roughly a dozen different projects that countries that have built nuclear weapons — the United States, Russia, China, Britain, France, Israel, India and Pakistan — all had to grapple with, in some form. An I.A.E.A. report last May listed five fewer categories of such technical information.
The inspectors’ report cited:
– Documents suggesting that Iran “was working on a project to secure a source of uranium suitable for use in an undisclosed enrichment program” to make bomb fuel.
– Evidence that Iran “had been provided with nuclear explosive design information.”
– Information that it worked on experiments with conventional explosives to compress metal into an incredibly dense mass suitable to start a chain reaction.
– Documentation of “at least 14 progressive design iterations” for a missile warhead to deliver an atomic warhead to a distant target.
The report was produced under Yukiya Amano, a former Japanese diplomat who has run the I.A.E.A. for nearly two years, and addressed to the agency’s board of governors and the United Nations Security Council. In it, Mr. Amano said that inspectors had amassed “over a thousand pages” of documents, presumably leaked out of Iran. He said they showed “research, development and testing activities” on technologies that would be useful in designing a nuclear weapon.
He said “a number of individuals” involved in Iran’s activities had provided information described as “consistent” with the intelligence from “more than 10” other countries, which it did not name, including some demonstrating Iranian “manufacturing techniques for certain high explosive components.”
A senior Obama administration official briefing reporters on Tuesday pointed to the I.A.E.A.’s evidence of work on detonation systems, including a special type of spherical initiation system that implodes a nuclear core with tremendous precision. “It’s a very telltale sign of nuclear weapons work,” he said.