Iran: Heading toward a nuclear show-down?
This looks set to be a critical week for diplomatic efforts to rein in Iran's nuclear programme. The UN's nuclear watchdog - the International Atomic Energy Agency (IAEA) - is due to release a report that is expected to give many more details about the basis for its suspicions that Iran is seeking to develop a nuclear bomb.
As the publication date approaches there's been a flurry of diplomatic activity with noises from Israel - and even from Britain - that a military strike against Iran cannot be ruled out.
As ever with Iran, the big powers are divided. Russia and China are eager that the IAEA pulls its punches, fearing that Iran could be driven into a corner.
Even the Iranians, who continue to insist that they have no desire to have nuclear weapons, have weighed in, claiming that the leaked contents of the IAEA report are "fabrications".
For some years, the IAEA has been warning of its concerns that Iran has been undertaking research related to nuclear weapons. Until now, the details have always been sketchy. There have been fears about "undisclosed nuclear activities involving military related organisations", including explosives research to enable the initiation of a nuclear chain reaction.
This week's report is expected to contain a specific annexe detailing what the agency believes the Iranians may be up to.Intelligence reports
A flurry of leaked reports suggest that there will be details suggesting Iran's military nuclear research programme continued after 2003 - the point when US intelligence agencies believe that such work was halted due to international pressure. Foreign scientists are said to have played a key part in some of Iran's technological breakthroughs.
You will notice that I have been careful to use words like "suggest" and "indicate" because the IAEA has had very limited access to Iran's nuclear programme and the Iranians themselves have been far from helpful in answering the agency's questions.
The main source of the IAEA's material has been the intelligence agencies of several countries. The IAEA has not been able to gather the material itself and the pieces of information with which it has been supplied have been obtained and selected by others.
However, there does seem to have been something of a sea-change within the IAEA itself - a feeling that the full information that it does have on Iran's alleged weapons activities should now see the light of day.
Nonetheless, the IAEA is unlikely to be able to make a definitive judgement as to exactly where the Iranians are along the road towards a bomb.More diplomacy?
Timelines here are crucial. Indeed, if you look back over the history of the diplomatic battles with Iran, timelines seem to be almost infinitely flexible.
The Israelis, who see an Iranian bomb as an existential threat, have frequently shouted the loudest, but there are generally moments of high anxiety - often leading up to crucial IAEA or UN meetings - after which things calm down again.
Western diplomats take the view that Iran could still be up to three years away from having a bomb, though its research effort has been making steady, albeit slow, progress.
The fuss now centres on this IAEA report and what may come after it. One option would be a full-scale referral to the UN Security Council with the possibility of further economic sanctions. Alternatively, Iran could be given some notice period within which to answer the IAEA's concerns, after which it might be harder for Moscow and Beijing to block a referral to New York.
For now, the diplomatic track probably still has some way to run. Amidst Europe's economic problems, the US end-game in Iraq and Afghanistan, an election looming in Washington and so on, there seems little real enthusiasm for a military option.How effective?
There are also doubts about just what a military strike would achieve, even if "successful". It might only delay Iran's quest for a bomb, while at the same time confirming its usefulness.
Some US reports suggest there are fears of unilateral Israeli military action, though this could just be another attempt to ratchet up the pressure on Tehran. In that sense, this is just one more stage in a familiar crisis.
However, in one important sense things have changed. The broader upheavals in the Middle East - "the Arab Spring" - leave both Israel and Iran uncertain and more isolated. Israel has lost an ally in the Mubarak administration in Egypt and Iran could well be on the way to losing its only steadfast friend, the Syrian government of President Basher al-Assad.
Uncertainty and isolation can influence decision-making in strange ways. This is not the final chapter in the saga of Iran's nuclear programme, but then, no book lasts forever.