Relying on Computer, U.S. Seeks to Prove Iran's Nuclear Aims

Willian Broad and David Sanger, The New York Times:

In mid-July, senior American intelligence officials called the leaders of the international atomic inspection agency to the top of a skyscraper overlooking the Danube in Vienna and unveiled the contents of what they said was a stolen Iranian laptop computer.

The Americans flashed on a screen and spread over a conference table selections from more than a thousand pages of Iranian computer simulations and accounts of experiments, saying they showed a long effort to design a nuclear warhead, according to a half-dozen European and American participants in the meeting.

The documents, the Americans acknowledged from the start, do not prove that Iran has an atomic bomb. They presented them as the strongest evidence yet that, despite Iran's insistence that its nuclear program is peaceful, the country is trying to develop a compact warhead to fit atop its Shahab missile, which can reach Israel and other countries in the Middle East.

The briefing for officials of the United Nations' International Atomic Energy Agency, including its director Mohamed ElBaradei, was a secret part of an American campaign to increase international pressure on Iran. But while the intelligence has sold well among countries like Britain, France and Germany, which reviewed the documents as long as a year ago, it has been a tougher sell with countries outside the inner circle.

The computer contained studies for crucial features of a nuclear warhead, said European and American officials who had examined the material, including a telltale sphere of detonators to trigger an atomic explosion. The documents specified a blast roughly 2,000 feet above a target - considered a prime altitude for a nuclear detonation.

Nonetheless, doubts about the intelligence persist among some foreign analysts. In part, that is because American officials, citing the need to protect their source, have largely refused to provide details of the origins of the laptop computer beyond saying that they obtained it in mid-2004 from a longtime contact in Iran. Moreover, this chapter in the confrontation with Iran is infused with the memory of the faulty intelligence on Iraq's unconventional arms. In this atmosphere, though few countries are willing to believe Iran's denials about nuclear arms, few are willing to accept the United States' weapons intelligence without question.

"I can fabricate that data," a senior European diplomat said of the documents. "It looks beautiful, but is open to doubt."

Robert G. Joseph, the under secretary of state for arms control and international security, who led the July briefing, declined to discuss any classified material from the session but acknowledged the existence of the warhead intelligence. He called it one of many indicators "that together lead to the conclusion Iran is pursuing a nuclear weapons capability."

Even if the documents accurately reflect Iran's advances in designing a nuclear warhead, Western arms experts say that Iran is still far away from producing the radioactive bomb fuel that would form the warhead's heart. American intelligence agencies recently estimated that Iran would have a working nuclear weapon no sooner than the early years of the next decade.

Still, nuclear analysts at the international atomic agency studied the laptop documents and found them to be credible evidence of Iranian strides, European diplomats said. A dozen officials and nuclear weapons experts in Europe and the United States with detailed knowledge of the intelligence said in interviews that they believed it reflected a concerted effort to develop a warhead. "They've worked problems that you don't do unless you're very serious," said a European arms official. "This stuff is deadly serious." READ MORE

In fact, some nations that were skeptical of the intelligence on Iraq - including France and Germany - are deeply concerned about what the warhead discovery could portend, according to several officials. But the Bush administration, seeming to understand the depth of its credibility problem, is only talking about the laptop computer and its contents in secret briefings, more than a dozen so far. And even while President Bush is defending his pronouncements before the war about Iraq's unconventional weapons, he has never publicly referred to the Iran documents.

R. Nicholas Burns, the under secretary of state for political affairs, who has coordinated the Iran issue with the Europeans, also declined to discuss the intelligence, but insisted that the Bush administration's approach was one of "careful, quiet diplomacy designed to increase international pressure on Iran to do one thing: abandon its nuclear weapons designs and return to negotiations with European countries."

Until now, there has been only one official reference to them: a year ago in a conversation with reporters, Colin L. Powell, then secretary of state, briefly referred to new, missile-related intelligence on Iran. Since then, reports in The Wall Street Journal, The Washington Post and other publications have revealed some details of the intelligence, including that the United States has obtained thousands of pages of Iranian documents on warhead development.

In interviews in recent weeks, analysts and officials from six countries in Europe and Asia revealed a more extensive picture of the intelligence briefings. In turn, several American officials confirmed the intelligence. All who spoke did so on the condition of anonymity, saying they had pledged to keep the intelligence secret, though it is being discussed by an array of senior government officials and International Atomic Energy Agency board members.

Officials said scientists at the American weapons labs, as well as foreign analysts, had examined the documents for signs of fraud. It was a particular concern given the fake documents that emerged several years ago purporting to show that Saddam Hussein had sought uranium from Niger. Officials said they found the warhead documents, written in Persian, convincing because of their consistency and technical accuracy and because they showed a progression of developmental work from 2001 to early 2004.

Within the United States government, "the nature and the history of the source has left everyone pretty confident that this is the real thing," said a former senior American intelligence official who was briefed on the laptop.

But one nongovernment expert cautioned that the intelligence could simply represent the work of a faction in Iran. "What we don't know is whether this is the uncoordinated effort of a particularly ambitious sector of the rocket program or is it, as some allege, a step-by-step effort to field a nuclear weapon within this decade," said Joseph Cirincione of the Carnegie Endowment for International Peace, who said he had not seen the secret documents.

The Iranians themselves deny any knowledge of the warhead plans. "We are sure that there are no such documents in Iran," Ali A. Larijani, secretary of the Supreme National Security Council and the country's chief nuclear negotiator, said in an interview in Tehran. "I have no idea what they have or what they claim to have. We just hear the claims."

As a measure of the skepticism the Bush administration faces, officials said the American ambassador to the international atomic agency, Gregory L. Schulte, was urging other countries to consult with his French counterpart. "On Iraq we disagreed, and on Iran we completely agree," a senior State Department official said. "That gets attention."

Inspectors and Secret Sites

For years, American intelligence agencies argued that Iran was hiding a range of nuclear facilities. Then, in February 2003, inspectors from the International Atomic Energy Agency went to Iran and confirmed reports of two secret sites under construction that could make concentrated uranium and plutonium, standard fuels for nuclear arms. At Natanz, in central Iran, they found preparations for more than 50,000 whirling centrifuges meant to purify uranium. At Arak, to the west, they found construction of a heavy-water plant and reactor meant to make plutonium.

Iran insisted the sites were for conducting peaceful research and making fuel for nuclear power, and were kept secret to evade American-led penalties on sales of atomic technology to Iran.

Over time, a string of revelations challenged that explanation, even as inspectors eventually uncovered at least seven secret nuclear sites.

In August 2003, agency inspectors discovered traces of uranium concentrated to the high levels necessary for a bomb, rather than the low levels for a power-producing reactor. Some of the uranium was shown to have arrived in Iran on nuclear equipment purchased from Pakistan, but a European diplomat disclosed that the origin of the rest was still a mystery.

Then there were questions about what Iran had obtained from the atomic black market run by Abdul Qadeer Khan, the Pakistani rogue nuclear engineer. Iran has acknowledged buying from Dr. Khan, but the extent of those dealings is still under investigation.

By late 2003, many government and nongovernment experts agreed that Iran was rapidly progressing. "Most people," said Gary Milhollin, director of the Wisconsin Project on Nuclear Arms Control in Washington, "believed that they had mastered the essential capabilities and had the potential to develop what they needed to make a bomb."

Diplomacy aimed at defusing Iran moved haltingly. Tehran agreed to suspend the enrichment of uranium as it negotiated with the West over the fate of its atom program, but months later began making uranium hexafluoride, the raw material for enrichment.

If Iran hid parts of its atomic program, it boldly displayed its missiles. And in August 2004, it conducted a test that deepened suspicions that it was at work on a nuclear warhead.

Tehran test-fired an upgraded version of the Shahab - shooting star in Persian - in a flight that featured the first appearance of an advanced nose cone made up of three distinct shapes. Missile experts noted that such triconic nose cones have great range, accuracy and stability in flight, but less payload space. Therefore, experts say, they have typically been used to carry nuclear arms.

Iran insists it is pursuing only peaceful energy, and notes that nations like Japan, South Korea and Brazil have advanced civilian nuclear programs and sophisticated missiles, but have been aided by the West in building their programs rather than being accused of trying to make atomic warheads.

"Second-class countries are allowed to produce only tomato paste," said Mr. Larijani, Iran's nuclear negotiator. "The problem is that Iran has come out of its shell and is trying to have advanced technology."

A Laptop's Contents

American officials have said little in their briefings about the origins of the laptop, other than that they obtained it in mid-2004 from a source in Iran who they said had received it from a second person, now believed to be dead. Foreign officials who have reviewed the intelligence speculate that the laptop was used by someone who worked in the Iranian nuclear program or stole information from it. One senior arms expert said the material was so voluminous that it appeared to be the work of a team of engineers.

Without revealing the source of the computer, American intelligence officials insisted that it had not come from any Iranian resistance groups, whose claims about Iran's nuclear program have had a mixed record for accuracy.

In July, as the Bush administration began stepping up the pressure on the United Nations to take punitive action against Tehran, it decided to brief Dr. ElBaradei on the contents of the laptop. The session on July 18 on the top floor of the American mission in Vienna was a meeting of former rivals. Before the Iraq war, Dr. ElBaradei had attracted the wrath of the Bush administration by declaring that his agency had found no evidence that Saddam Hussein was reconstituting his nuclear program. And the administration had tried to oust Dr. ElBaradei, an Egyptian, from his post, partly because they found him insufficiently tough on Iran.

The briefing primarily revealed computer simulations and studies of various warhead configurations rather than laboratory work or reports on test flights, according to officials in Europe and the United States. But one American official said notations indicated that the Iranians had performed experiments. "This wasn't just some theoretical exercise," he said.

In an interview, Dr. ElBaradei, who won the Nobel Peace Prize in October, declined to discuss the secret briefing.

Assessing just how far the Iranians have gone from plan to product is difficult. "It's easy to fall into the trap of thinking that beautiful pictures represent reality," a senior intelligence official said. "But that may not be the case."

One major revelation was work done on a sphere of detonators meant to ignite conventional explosives that, in turn, compress the radioactive fuel to start the nuclear chain reaction. The documents also wrestled with how to position a heavy ball - presumably of nuclear fuel - inside the warhead to ensure stability and accuracy during the fiery plunge toward a target. And a bomb exploding at a height of about 2,000 feet, as envisioned by the documents, suggests a nuclear weapon, analysts said, since that altitude is unsuitable for conventional, chemical or biological arms.

After more than a year of analysis, questions remain about the trove's authenticity. "Even with the best intelligence, you always ask yourself, 'Was this prepared for my eyes?' " one American official said. Several intelligence experts said that a sophisticated Western spy agency could, in theory, have produced the contents of the laptop. But American officials insisted there was no evidence of such fraud.

Gary Samore, the head of nonproliferation at the National Security Council in the Clinton administration, who recently directed a report on Iran that drew on interviews with government officials in many nations, said, "The most convincing evidence that the material is genuine is that the technical work is so detailed that it would be difficult to fabricate."

An Unclassified Briefing

In August and September, as the United States was preparing for a showdown vote at the International Atomic Energy Agency on whether to recommend action by the United Nations Security Council against Iran, the Bush administration stepped up its campaign.

The United States rarely shares raw intelligence outside a small circle of close allies. But it decided to disseminate a shortened version of the secret warhead briefing. Mr. Joseph and his colleagues presented it to the president of Ghana and to officials from Argentina, Sri Lanka, Tunisia and Nigeria, among other nations.

But the administration felt uncomfortable sharing any classified intelligence with another ring of countries. For them, it developed the equivalent of the white paper on Iraq that Britain and the United States published before the Iraq war. The 43-page unclassified briefing includes no reference to the warhead documents, but uses commercial satellite photos and economic analysis to argue that Iran has no need for nuclear power and has long hidden its true ambitions.

Analysts from the Los Alamos National Laboratory and the Pacific Northwest National Laboratory wrote the briefing paper for the State Department, which distributed it widely. In graphic detail, the paper offers a tour of the previously hidden sites, saying, for instance, that a "dummy" building at the centrifuge plant in Natanz hides a secret entrance ramp to an underground factory.

The briefing asserted that Iran did not have enough proven uranium reserves to fuel its nuclear power program beyond 2010. But it does have enough uranium, the report added, "to give Iran a significant number of nuclear weapons."

The briefing landed with something of a thud. Some officials found its arguments superficial and inconclusive. "Yeah, so what?" said one European expert who heard the briefing. "How do you know what you're shown on a slide is true given past experience?"

Even so, the American campaign helped produce a consensus among International Atomic Energy Agency board members, although a fragile one. On Sept. 24, the board passed the resolution against Iran by a vote of 22 to 1, with 12 countries abstaining, including China and Russia.

It cited Iran for "a long history of concealment and deception" and repeated failure to live up to its obligations under the Nuclear Nonproliferation Treaty, which it signed in 1970. The resolution said Iran's failings had set it up for consideration by the Security Council for possible punishment with economic penalties, though it left the timing of the referral to a future meeting.

Manouchehr Mottaki, Iran's foreign minister, denounced the resolution as "illegal and illogical" and the result of a "planned scenario determined by the United States."

Debating the Next Step

On Thanksgiving, Nov. 24, the board of the international atomic agency plans to meet again to confront the Iranian nuclear question - and decide whether to take the next step and send the issue to the Security Council.

The Bush administration is confident in its evidence. "There is not a single country we deal with that does not believe Iran is seeking a nuclear weapon," said Mr. Burns, the under secretary of state.

The Iranians have taken steps to forestall any penalties. After months of delays, they have allowed inspectors into a secret military site, shared more information about the history of their program, and signaled a willingness to reopen negotiations, even while vowing to continue turning raw uranium into a gas that can be enriched. Those steps may convince some atomic agency board members. And at least two countries rotating onto the board for the next meeting - Cuba and Syria - are almost certain to defy Washington. (In September, only Venezuela voted with Tehran.)

Given those politics, the fresh intelligence that the United States says proves Iran's true intentions may not be pivotal in the long confrontation with Tehran. One reason is that the United States has so far refused to declassify the warhead information, making it impossible to seek a detailed explanation from the Iranians.

Dr. ElBaradei said his agency was bound to "follow due process, which means I need to establish the veracity, consistency and authenticity of any intelligence, and share it with the country of concern." In this case, he added, "That has not happened."

European nations and the international atomic agency are now working out details of a new proposal that offers Tehran the chance to conduct very limited nuclear activities in Iran, but move any enrichment of uranium to Russia - part of the effort to keep the country from obtaining the nuclear fuel that could go atop the Shahab missile.

Some European diplomats are concerned that confronting the Iranians with strong evidence of the warhead studies could cause Tehran to abandon negotiations with the West, expel international inspectors and move forward with its plans, whatever they may be.

"It's a card that will explode the system in place, so the question becomes when and how you play it," a senior European diplomat said. "If there is information that can serve to make progress with the Iranians, without blowing up the system, that's better."

Dexter Filkins contributed reporting from Tehran for this article.