Many doubts still surround the veracity and details of the alleged plot orchestrated by senior figures in Iran to assassinate Saudi Arabia's ambassador to the United States. A mix of court hearings and media investigation following the arrest of a chief suspect suggests that action by US federal authorities halted an operation that sought to explode a bomb in a Washington restaurant, killing Adel al-Jubeir (and presumably others).
Even in the absence of clinching evidence of what was underway and the degree of involvement of the Iranian Revolutionary Guards Corps (IRGC), the assassination "plotline" has developed a life of its own and led to increasingly strident calls for action by Washington against Tehran (see "Iran and America: components of crisis", 13 October 2011). After all, many argue, this would have been an attack on the United States mainland and capital city and thus comparable in terms of intent to 9/11 (even if the scale were to prove much smaller). Moreover, the operation has an added potency in that the notional plan was organised by a state rather than by a sub-state group (albeit those behind 9/11 were harboured by Afghanistan's Taliban rulers).
Barack Obama's administration is running with this tough line. Some of its officials extend the condemnation of Iran by seeing the plot as part of a wider Iranian strategy of aggressive transnational operations (see "U.S. Fears More Plots from Iran's Quds Force", Reuters, 20 October 2011).
In this atmosphere of escalating attitudes and rhetoric, a note of caution is appropriate. The basis of the arrests is still in doubt, and the nature of the overall plot little resembles the kind of sophisticated foreign operations associated with the IRGC and its elite Qods brigade (see Gareth Porter, "The (Dis)information war gets ugly", Asia Times, 18 October 2011).
The pressure on Iran is increasing, and the Obama administration is prepared to risk adopting a stance that aids those elements in Tehran's power-elite most in need of an external enemy to advance their domestic interests. In turn this creates space for more intransigent voices in the United States to talk seriously of war.
William Kristol speaks for many:
"We can strike at the Iranian Revolutionary Guard Corps (IGRC), and weaken them. And we can hit the regime's nuclear weapon program and set it back. Lest the administration hesitate to act over lack of support at home, Congress should consider authorizing the use of force against Iranian entities that facilitate attacks on our troops, against IRGC and other regime elements that sponsor terror, and against the regime's nuclear weapons program. The next speech we need to hear from the Obama administration should announce that, after 30 years, we have gone on the offensive against this murderous regime, and the speech after that can celebrate the fall of the regime and offer American help to the democrats building a free and peaceful Iran" (see William Kristol, "Speak Softly...and Fight Back", Weekly Standard, 24 October 2011).
This call for confrontation reflects an enduring sentiment in US security and foreign-policy circles: deep frustration over an unexpected consequences of the Iraq war - a strengthened Iran with increased regional influence.
The Obama administration is unlikely to oblige at a time when domestic economic issues are at the forefront of its concerns. But this is not the end of the story, for a growth in tension between the US and Iran can itself acquire its own momentum in a way that creates either an "accidental" escalation that no one consciously chooses or an opportunity for Israel (perhaps against the advice of some of its senior military) to launch an attack of its own (see "Israel vs Iran: the risk of war", 11 June 2010).
The advocates of war are in thrall to a seductive logic. They assume that damage to the Iranian nuclear programme and the IRGC would so weaken the regime and undermine its prestige as to expose it to overthrow by Iran's people. A few days of war would in effect end the problem of Iran that has flummoxed Washington for three decades.
The US's recent experience in the region makes this mindset even more extraordinary. The overthrow of the Taliban in Afghanistan created the firm belief by December 2001 that an Afghan transition to a peaceful pro-western democracy had begun; instead it has led to ten years of war with no end in sight. The toppling of the Saddam Hussein regime in Iraq similarly fuelled the expectation by May 2003 that Iraq would move rapidly to a free-market economy run by pro-western democrats protected by US bases; instead what followed was a seven-year war that has left endemic instability and violence - and a more influential Iran (see "America in Iraq: power, hubris, change", 2 September 2010).
Many military analysts in the United States, Israel, Britain and elsewhere employ two powerful arguments to advise against any move towards war with Iran.
First, many radicals in Iran would actually welcome an Israeli or American attack. They are confident that the results would be beneficial to them: a substantial majority of Iranians would rally to the regime's defence; thousands of recruits would flock to the IRGC; Iran would withdraw from the nuclear non-proliferation treaty and work as fast as possible to develop a deterrent; a series of actions and initiatives would make life unsettling for the United States and its allies in Afghanistan, Iraq and the emirates of the western Gulf.
Second, a substantial attack on Iran would be the start - not the finish - of a war. Iran's response in ensuing months and years would require more intensified assault. The conflict would be asymmetrical: conventional bombing (principally air and missile power) versus irregular and flexible tactics that would prove very difficult to counter (see "Asymmetric war: Iran and the new normal", 8 July 2010).
These arguments have little or no effect on the hawks. The tensions around Iran now resemble those of 2005-06 when war also seemed a real possibility (see "The next Iran war", 16 February 2006). There is a current, palpable unease that a new time of crisis is approaching that opens the danger of a sudden descent into conflict. The delusion that there is an easy military solution to very hard circumstances adds to the peril.
There is an urgent need for calm analysis, clear minds, and creative thinking to find a rational and peacable way forward. It is far from evident that the most important representatives of western political leadership are sufficiently armed with these essential attributes.