Iranian President Mahmoud Ahmadinejad's government is keeping the West guessing as how its nuclear program is developing.

Story highlights

Experts and policy-makers differ about the time Iran would need to develop a nuclear weapon

Islamic Republic's supreme leader said acquiring a nuclear weapon would be "un-Islamic"

Israel, U.S. face a quandary over when Iran's nuclear "development" can be thwarted

Intelligence agencies might have problems knowing if Iran has reached key nuclear stages

CNN  — 

There are “red lines,” a “window of opportunity,” the risk of a “zone of immunity,” and plenty of other cryptic terms about Iran’s nuclear program. What does it involve? Where is it leading? How and when should it be stopped or restrained?

Ordinary mortals can’t know where those red lines lie; when the “weaponization” of Iran’s nuclear material might be imminent; even what Iran’s real intentions are. Experts and policy-makers differ about the time Iran would need to develop a nuclear weapon, the space for diplomacy, whether Iran wants a nuclear weapon as an instrument of deterrence or would use it pre-emptively. Or even whether it really is hell-bent on acquiring one.

James Clapper, the U.S. Director of National Intelligence, told the Senate Intelligence Committee in January that Iran was “keeping open the option to develop nuclear weapons…We do not know, however, if Iran will eventually build nuclear weapons.”

Israel’s Prime Minister, Benjamin Netanyahu, has no doubt. He told an audience in Washington this week: “Amazingly, some people refuse to acknowledge that Iran’s goal is to develop nuclear weapons…..This duck is a nuclear duck and it’s time the world started calling a duck a duck,” he said.

The Islamic Republic’s supreme leader, Ayatollah Ali Khamenei, repeated recently that acquiring a nuclear weapon would be “un-Islamic” (in 2005 he issued a fatwah that “the production, stockpiling and use of nuclear weapons are forbidden under Islam, and that the Islamic Republic of Iran shall never acquire these weapons.”) Was he sincere? Bluffing? Or looking for a way to begin a graceful climb-down?

According to both governments, the United States and Israel are unified in their goal. “We are committed, as Israel is, to preventing Iran from acquiring a nuclear weapon,” said White House spokesman Jay Carney shortly before Netayahu’s visit.

But how to measure that goal? The U.S. Defense Department’s Strategic Guidance, published in January, emphasized efforts “to prevent Iran’s development of nuclear weapon capability.”

The quandary: at what point must that “development” be thwarted before it’s too late. When Iran has acquired enough low-grade uranium that could if enriched make one weapon? When there is evidence that the process of such enrichment is underway? When it has made enough highly enriched uranium for a nuclear warhead? When it has built the weapon? When it has a viable delivery system? (It already has a wide range of ballistic missiles.) How long might each of these phases take?

Even the best intelligence agencies might have problems finding out when each of those stages is imminent. After all, an accurate reading of Iraq’s Weapons of Mass Destruction program seemed elusive ten years ago.

Policy-makers in Washington say Iran continues to move steadily toward the capability to build a bomb. “It has the scientific, technical and industrial capacity to eventually produce nuclear weapons, making the central issue its political will to do so,” Clapper told the Senate hearing.

But in the meantime, President Obama says, there is still a window for diplomacy, and he has welcomed the scheduled resumption of multilateral talks (involving the United States, the European Union, Russia and China) with Iran.

“This notion that somehow we have a choice to make in the next week or two weeks or month or two months is not borne out by the facts,” the President told a news conference Tuesday.

For the Israeli government, the timetable is more urgent, and it always has been. Netanyahu pointedly told the American Israel Public Affairs Committee Sunday: “We’ve waited for diplomacy to work. We’ve waited for sanctions to work. None of us can afford to wait much longer.”

The initial enrichment process – because it is monitored and reported by International Atomic Energy Agency - is the least difficult step in the chain to track (though that is not to suggest it is easy.) According to the latest IAEA report, published February 24th, Iran had tripled its production of 20% U-235 at the Fordow Fuel Enrichment Plant and Natanz - to some 11 kilograms a month. Uranium enriched at 20% is typically used for hospital isotopes and research reactors, but is also seen as a short-cut toward the 90% enrichment required to build nuclear weapons. Nuclear experts say Iran’s supply is far greater than it would need for peaceful purposes.

Even before the February report, Olli Heinonen, a former deputy director-general at the IAEA and now at Harvard’s Belfer Center for Science and International Affairs, wrote in Foreign Policy that Iran would be able to produce 15 kilograms of 20% enriched uranium a month, which he said was ‘“alarming.”

The International Institute of Strategic Studies estimates that Iran now has a stockpile of some 110 kilograms of 20% U-235, and says that “Iran’s decision to build a relatively small enrichment facility without informing the IAEA suggested that Fordow was intended to be used to quickly and securely make highly enriched uranium for nuclear weapons.” The Bipartisan Policy Center in Washington says that “Iran could produce 20 kilograms of highly enriched uranium, enough for a weapon, in as little as 43 days.”