US officials weigh Iran's nuclear weapons capability

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Iran now has enough fissile material to build a nuclear bomb, according to the most senior US military official, Chairman of the Joint Chiefs of Staff Adm. Mike Mullen.

His comment on CNN echoes a recent assessment by the UN's nuclear watchdog on Iran's enrichment program. Iran has repeatedly denied seeking nuclear weapons.

"We think they do, quite frankly," Mullen said on State of The Union with John King. "Iran having a nuclear weapon, I believe ... is a very, very bad outcome for the region and for the world."

Defense Secretary Robert Gates said Sunday, however, that Iran wasn't close to having a nuclear bomb, meaning that there was still time for diplomacy and economic sanctions to have an effect. He told NBC that Iran wasn't even close to having a stockpile of uranium that could be used in a bomb, reports the Los Angeles Times. He pointed out that the global slump in oil has hurt Iran and could give the US and its allies greater leverage there.

TIME reports that a spokesman for Admiral Mullen later clarified that he was referring to low-enriched uranium, which is not sufficient in itself to create a bomb. US intelligence agencies suspect Iran is creating the means to build a bomb under the cover of a nuclear energy program – a crucial distinction.

In its February report, the International Atomic Energy Agency said that Iran had roughly 1 metric ton of low-enriched uranium, which could be enough to arm a warhead, the Guardian reported last month. This assessment came as a surprise because the agency had said in November that Iran had produced only 635 kilograms of the fissile material. Iran has blocked inspectors from a nuclear reactor near the town of Arak and refuses to open up its centrifuge manufacturing facility.

Newsweek correspondent Christopher Dickey writes that Iran hasn't crossed the red line known as "breakout," when it might pull out of the Nuclear Non-Proliferation Treaty (NPT) and expel UN inspectors. Such a provocation could start a war, given the implacable opposition by the US and others to a nuclear-armed Iran, the article reports.

What Iran has now achieved, says former inspector David Albright, of the Institute for Science and International Security, is "breakout capability." Perhaps that's all Iran really wants: enough mastery of enrichment to keep the world guessing about its nuclear defenses without provoking massive retaliation. IAEA Director-General Mohamed ElBaradei tends toward this view. But as Albright says, "We just don't know … I think people should be worried."

The Financial Times reports that a Washington think tank staffed by senior foreign-policy advisers to President Obama has recommended tougher sanctions on Iran. The Washington Institute for Near East Policy warns that Iran is seeking Russian surface-to-air missiles and that Israel may try to hit Iran's nuclear facilities before any Russian defenses are installed. US envoy Dennis Ross was among those involved in preparing the institute's report, though he is no longer there.

Arguing that such a strike "might only slow Iran temporarily" and that the US itself may pay a "high price" from a backlash across the region, the report says the administration should broaden a campaign to dissuade international banks from doing business with Iran to include industrial and trading companies….

The report says that if the $800m (€631m, £558m) Russian missile sale goes ahead "the US should provide Israel with the capabilities to continue to threaten high value Iranian targets" with more modern aircraft and use such an offer "to gain leverage in pressuring Russia not to transfer the S-300".

The Wall Street Journal reports that Secretary of State Hillary Clinton will be discussing Iran's nuclear program this week during a Middle East tour, her first to the region. Talks with Russia may touch on a suggestion that Moscow work harder to curb Iran's nuclear ambitions in return for a slowdown in the US missile-shield program that has irked Russia.

An expert told Ynet, an Israeli website, that Iran was only a few months away from creating a nuclear bomb. Ephraim Asculai, a senior researcher at Tel Aviv University's Institute for National Security Studies, said he agreed with the IAEA's view that Iran hadn't yet produced enough weapons-grade uranium.

"The uranium produced by the Iranians today is not good enough for a nuclear bomb. And in any event, I believe that even if Iran has reached an amount of high quality uranium which would be enough for one bomb, it won't start creating it immediately. It will have to produce a slather of uranium before creating bombs."

Last month, Adm. Dennis Blair, the US director of national intelligence, told Congress that Iran had imported some weapons-grade material and was trying to enrich its own, but that the consensus view was that it still wasn't able to make a bomb, says Reuters. US intelligence agencies have previously concluded that Iran suspended a program to develop a nuclear warhead.