The seizure of 15 British sailors and marines has dragged Anglo-Iranian relations — already tense with the impasse over Tehran’s nuclear ambitions — to yet another low. Some have conjectured that the seizure of the British naval patrol is connected to the imminent vote in the UN Security Council on the next phase of sanctions. But this just reflects a tendency in the West to analyse Iran’s behaviour exclusively through the prism of the nuclear crisis.

Others have sought to emphasise the accidental nature of the seizure. This incident, it is argued, is a misunderstanding on a par with the arrest of the British marines from the Shatt al-Arab waterway in 2004, which was resolved through patient diplomacy with what was then the reformist Government in Tehran.

But the evidence in this present trouble suggests it was no accident. It is more likely to reflect a shift in internal Iranian politics — the renewed confidence of the Islamic Revolutionary Guards Corps (IRGC), the military wing of the Islamic revolution, strengthened at home and abroad.

For abroad, we should read Iraq. Events there, especially after George Bush’s announcement of the “surge”, have driven this particular diplomatic incident. Ignoring the advice of the Baker-Hamilton report, President Bush decided, in an exercise in intellectual acrobatics only an ideologue could achieve, that Iran’s influence in Iraq was insufficient to warrant engagement, but nonetheless important enough to necessitate confrontation. Mr Bush determined that now was the time to get tough with Iran, and in particular the al-Quds force of the IRGC.

That force supplied arms and explosives to Shia militias, some of which found its way into roadside bombs against coalition forces. The commanders on the ground suspected al-Quds of having encouraged these attacks, so Mr Bush decided that it was time to change US forces’ terms of engagement with Iran. The immediate consequences were soon felt, as Iranian diplomats, intelligence officials and IRGC operatives suddenly found themselves the targets of sudden raids and abductions. In one dramatic early morning raid at an IRGC establishment in Irbil, a number were abducted.

The private reaction of some Iranian officials at this raid proved revealing. Basically, they thought, these guardsmen were clearly up to no good, they were caught and that was that. What rankled however, was that these operatives just simply disappeared. These US actions, however, seemed to have the desired effect; IRGC activities subsided considerably. Yet while the volume had suddenly decreased, whispers of retaliation were soon being heard on websites affiliated to the Guards. Indeed, there could be little doubt that that the IRGC intended to respond in kind. This was given extra weight when, in his new year speech, the Supreme Leader, Ayatollah Khamenei said that Iran may have to respond to “illegal acts” with acts of its own. This was two days before the seizure of the British sailors. A coincidence perhaps, but a convenient one for those in the IRGC looking for a green light.

Strikingly, this latest action took place in the midst of the Persian new year, a time when Iran shuts down for two weeks. Those who may have urged caution would have been faced with a fait accompli — the official Iranian insistence that the incident bears no relation to earlier developments in Iraq bears all the hallmarks of civil servants hurrying back from holiday to contain an otherwise dangerous situation.

The IRGC is less a fighting force and more a vast business conglomerate: some Iranian wits have argued that the real reason for the seizure was that the Royal Navy had happened upon an IRGC smuggling operation. In forging its own revenue stream — an entrepreneurial spirit much encouraged by President Mahmoud Ahmadinejad — the IRGC has succeeded in developing an autonomy within the Iranian state.

This is not a development viewed with universal acclamation in Iran. Many political activists have vocally protested at what they see as the militarisation of Iranian life. Some senior figures have sought to challenge this growing domination by the Guards. The IRGC has served notice, at home and abroad, that it will not be pushed around, conveniently cloaking its actions in the flag of national indignation at this alleged British infringement of territorial integrity.

The British, of course, serve as an easy target: they are regarded as less temperamental than their American cousins but alleging British perfidy to an Iranian audience, remains, for historical reasons, an easy sell. Thumbing one’s nose at Britain remains the easiest way to score nationalist “brownie” points, in much the same way as being tough on Iran scores electoral points in the US.

However, the diversity of opinion in Iran’s political elites and the suspicion with which the IRGC is often regarded invites subtle, if forceful diplomacy. It needs to be delivered with clarity and a sense of purpose — ideally in unison with EU allies — which should leave Iranians of all political hues in no doubt of the seriousness of the situation.

This is not a time for hyperbole or mislaid threats. Nor should it be exploited by those with ulterior motives as a call to arms. Nothing would be more absurd; nothing would please the leadership of the IRGC more. The one significant difference with 2004 is that Britain now has an expanding cadre of Persian specialists whose primary focus is Iran. The armchair generals should take a back seat and let the professionals do their job.

Ali Ansari is director of the Institute of Iranian Studies, University of St Andrews and author of Confronting Iran

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