The events that have roiled Iran since its highly questionable presidential election are the product of a perfect storm, the confluence of several crises that simultaneously have come to a head.

Of these, the immediate electoral crisis might well be the least significant, insofar as it opposed two men - President Ahmadinehad and Mir Hossein Moussavi - who are less important that the array of forces that back them. More importantly, the events brought to the surface an old conflict that has now become unmanageable between the Islamic Republic’s two principal ruling factions. Their clash is nothing new, even if it was long ignored by Western policymakers single-mindedly focused on the nuclear issue.

On the one hand is the network coalesced around the Revolutionary Guards, breeding ground of second generation Islamic leaders that seek to preserve - if not radicalise - the Revolution’s ideals, master advanced technology such as nuclear energy, ensure Iran emerges as a regional power, and acquire greater financial and political assets within the system. On the other hand are the so-called pragmatic oligarchs of the Republic which gravitate around former president Hashemi Rafsanjani, rarely mentioned yet omnipresent, one of Iran’s most influential and wealthiest men. To date, the regime had managed to contain and channel this conflict through a convoluted electoral game with the Supreme Leader standing above the fray, co-opting both sides while favouring each in turn.

The third conflict involves the deepening socio-economic frustration of large swaths of the population whose confidence in the regime has dwindled over time.

The 12 July elections - and the way in which the regime dealt with them - brought all three crises to a head. The Supreme Leader broke the established rules of the game, clearly siding with one side and hurriedly validating Ahmadinejad’s re-election. Today’s effort to sideline the Rafsanjani clan through politically motivated arrests likely is but a foretaste of a far more ruthless and systematic political purge to come.

Time will tell whether the Islamic Republic can restore a semblance of stability in the short term. But a threshold has been crossed, and a return to calm will not be a return to the status quo ante. Already, the all-out conflict between Rafsanjani and Ahmadinejad is having ripple effects, as members of the harder-line camp with ties to the Revolutionary Guards express doubts, question regime decisions and seek to rein in the re-elected president. Among the country’s influential clerical corps, too, dissent is being heard, weakening yet another pillar of regime legitimacy.

Other effects undoubtedly will be felt, not least within the state’s defence and security organs: the paramilitary forces, the secret services and other political-financial networks of influence. The fault-line runs through each of these structures, which are key for the preservation of the Islamic Republic.

The regime must now deal with unprecedented internal rifts within the system even as also faces public demands for freedom and democracy far exceeding anything any of the presidential candidates can offer. The events of the last few weeks in this sense are a watershed - shaking the foundations of the regime, undercutting the Supreme Leader’s status, and exposing a deepening rift with the people.

It is a turning point in what could be a very long story - but a turning point nonetheless.

* Frédéric Tellier is Senior Iran Analyst at the International Crisis Group, www.crisisgroup.org