Iran’s decision to step up its nuclear programme raises three simple questions which are almost as difficult to answer as they are impossible to avoid.

What happens next now that Iran has broken United Nations seals from a controversial “pilot” nuclear facility?

How long would it take for Iran to build a bomb, and does it really want to do so?

Is the crisis going to lead to military action – and is there any way out?

Any answers to such questions are likely to be incomplete, biased or just downright wrong, but on an issue this important it would be irresponsible not to try out a little informed guesswork.

After all, Iran’s decision to start up research involving uranium enrichment – the process that can produce weapons grade material – could mark a decisive break with the west.

First, what happens now? Events over the next few days can be fairly easily predicted. After that things become more blurred.

On Thursday January 12, foreign ministers from Britain, France, and Germany – the so-called EU3 – will meet EU representative Javier Solana and call for an emergency meeting of the board of the International Atomic Energy Agency, the UN’s nuclear watchdog. The purpose of the IAEA meeting will be to refer the Iran dossier to the UN security council.

Any member has a right to call such an IAEA meeting – and it is likely to take place this month, in about two weeks time.

That would give Mohamed ElBaradei, the IAEA director general, enough time to compile a short report on Iran – something that the EU3 thinks will greatly bolster its case for referral.

After two years of trying to facilitate the talks, Mr ElBaradei has publicly said that his patience is running out. Just this week, Tehran spurned his last-ditch appeal not to start up the pilot enrichment project again. And his next report, which will be the basis for the IAEA discussions, is likely to break with his previous efforts, which have taken pains to be even-handed.

Instead, Mr ElBaradei is set to report that he has made “no progress” in persuading Iran to allow access to suspect sites or to hand over documents that could cast light on whether Tehran has sought to develop nuclear weapons.

The Iranians have already shown, but refused to hand over, to the IAEA a document that diplomats consider to be highly incriminating – a design given to Iran by Pakistan’s AQ Khan nuclear proliferation network in the 1980s, which appears to show how to cast enriched uranium into hemispheres. This is a process whose chief use is engineering a nuclear explosion.

Last weekend, all five members of the UN security council sent diplomatic demarches to Iran asking Tehran to give up the document.

That unity of purpose has led European diplomats to conclude that China and Russia are unlikely to oppose referring Tehran to the security council, although Moscow and Beijing may need additional convincing once the issue arrives in New York.

Preliminary talks at the UN have already begun on a first resolution or statement and are likely to intensify after the EU foreign ministers meeting. As a first step the UN resolution is likely to call on Iran to abide by the demands of the IAEA and ask Mr ElBaradei to report back, possibly within a month.

What happens next would depend on Iran’s response – in particular whether it decides to restart its entire nuclear programme, not just the pilot plant. Sanctions, including a possible UN ruling that Iran no longer has the right to nuclear enrichment, would be further down the path.

Western diplomats hope that this process will put enough pressure on Iran to persuade it to step back from the brink and give it enough time to do so. But the risk is that instead the whole crisis will be escalated.

As to how long it would take Iran to make a nuclear bomb, one estimate by London’s International Institute for Strategic Studies, puts the time at about five years. But if it was just the pilot plant that was active, it could be more like thirty to forty years.

When the Iranians shut down the pilot plant in 2004, it had only 164 centrifuges running, out of a total of 1,200 centrifuges that Iran had assembled, and some of them crashed.

So it is a hugely important issue whether Iran takes the next step to a full-blown resumption of uranium enrichment and gets all 1,200 centrifuges whirring again while assembling others.

On the question of whether Iran genuinely wants the bomb, the Islamic republic has always sworn that its aims are purely peaceful and that it is merely seeking to safeguard its energy security.

But Iran is internationally isolated, with a hostile US army on two of its borders. Meanwhile Israel, its sworn enemy, has long been a nuclear state. So some diplomats argue that Tehran wants to be within arm’s reach of nuclear capacity, with all the infrastructure needed to develop nuclear weapons without necessarily having the bomb itself.

Others – notably American officials – argue that AQ Khan’s involvement and Iran’s alleged interest in missile designs is powerful proof that Tehran wants to develop nuclear weapons.

Finally, is the crisis going to lead to some sort of military action? A US invasion and occupation of Iran is definitely not on the cards. Washington does not have the troops, money or diplomatic scope for such a course of action. “Military action is not on our agenda,” said British foreign secretary Jack Straw this week. “I don’t believe that in practice [it is] on anybody else’s agenda.” The dispute had to be resolved by “diplomatic and other non- military means,” he added.

But almost exactly a year ago, US Vice President Dick Cheney speculated openly about an Israeli strike on Iran. “Given the fact that Iran has a stated policy that their objective is the destruction of Israel, the Israelis might well decide to act first, and let the rest of the world worry about cleaning up the diplomatic mess afterwards,” he said in January 2005.

He was speaking of a time of relative hope, in the immediate aftermath of the EU3’s November 2004 agreement with Iran. Since then, things have got much darker and Iran’s President Mahmoud Ahmadi-Nejad has added to the tensions by calling for Israel to be “wiped off the map”.

There may still be solutions at hand. For six months, diplomats have been talking about a Russian proposal, not yet definitively rejected by Tehran, that would ensure that Iran carried out uranium enrichment not on Iranian territory but on Russian soil.

Many Europeans believe that any definitive end to the dispute would have to involve a “grand bargain” in which the US and Iran would take steps towards mutual diplomatic recognition. Mr ElBaradei had hoped that a temporary de facto suspension of Iran’s sensitive nuclear activities might grow into a more permanent entente between the various sides.

But at the moment, things are looking pretty grim. It’s one thing to try to answer the questions about Iran’s nuclear programme. It’s another to find grounds for optimism.

Copyright The Financial Times Limited 2018. All rights reserved.

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