At the time of writing, Iran was playing host to a critical moment in its history when, following Mahmoud Ahmadinejad’s victory in the country’s allegedly rigged presidential election, hundreds and thousands of Iranians piled on to the streets of Tehran to protest and in support of opposition candidate Mir Hossein Mousavi who was widely expected to take up office.

Such was the speed at which developments were occurring that the protests and rallying calls for a fresh election, in a manner reminiscent of – and not seen since – the 1979 Iranian revolution, quickly turned into an unprecedented concerted effort that, for the first time since theocratic Iran’s birth, put into serious question the authority of a regime which finds its credibility in tatters and its future on the brink.

Most critical of all for the international community is determining what impact all of this will have on the foreign policy challenges Iran presents to them. But to determine the foreign policy consequences of an Ahmadinejad or – should the protests materialise into it – a Mousavi presidency, it is first imperative to understand Iran’s complicated system of governance through which policies are determined. Most important of all is that it is the supreme leader, Ayatollah Ali Khamenei, who has the final say over matters of foreign policy and not the president.

Consequently, though Mousavi may not be victorious, this in and of itself should not be used to infer any major consequences for Iranian foreign policy. In any case, Mousavi is a former prime minister and a product of theocratic Iran rather than a challenge to it. It was Mousavi who was at the centre of the Iran hostage crisis and complicit in an operation that led to the current state of Iran-US relations. During his tenure as prime minister from 1981 to 1989, he initiated Iran’s nuclear programme and oversaw the massacre of thousands of political prisoners. Iran’s Barack Obama he is not.

The question that therefore must be asked is why then would the authorities embark upon the costly endeavour of keeping Ahmadinejad in power through any means possible? The answers may be found within the upper echelons of the regime where within the clerical, military, and political elite, a clash of ideologies, personal divisions and, ultimately, a struggle for power currently persists.

In sum, the battle is one between the hardliners and so-called reformists: Mousavi, two former popular and powerful presidents, Hojatoleslam Rafsanjani and Mohammad Khatami, together with the protesters, are up against Ahmadinejad, a 125,000-strong Revolutionary Guard (protectors of the theocracy), tens of thousands of fanatical Islamic volunteer militiamen called Basiji and a state machinery including the media and the judiciary. Critically, the latter group have the backing of the most powerful force in the country (the supreme leader, who, it should be noted, will have authorised any vote-rigging).

What now exists with Ahmadinejad in power is a seemingly impervious and evidently brutal vanguard against popular demands for reform and moderation; one made up of a collection of hard-line radical mullahs, revolutionary guards and an ultra-conservative political elite coalesced around Ahmadinejad himself. This Islamic fundamentalist elite is intent on, first, preserving the ideals of the 1979 revolution and, more widely, taking Iran from an Islamic republic to an Islamic government which takes its guidance from the will of the divine rather than the will of the people.

In treading down this road, theocratic Iran has openly committed itself to a course of nuclear capability, increased expansionism and support for terrorism. In doing so, its message is clear – Iran is a regional hegemon and this cannot be reversed. The country already has overreaching influence over proxies in Gaza and Lebanon, unmatched influence in Iraq and considerable hold over Syria. Iran may now seek to diversify and look at other ways of developing influence elsewhere, much to the fear of neighbouring Arab states who will in turn look to the west and, behind the scenes, to Israel to form some form of alliance against a common threat.

Increased Iranian expansionism, under the grip of continued and uncompromising radicalism equates with confrontation, division and uncertainty that dampens the recent impetus given by the Obama administration to US-Iran relations and the usually stagnant Middle East peace process. Iran will continue and will not relinquish its active support for Hamas and Islamic jihad in Gaza, prolonging the former’s isolation and suppressing any hopes for a negotiated peace plan; it will continue to arm them and Hezbollah in Lebanon in order to strengthen the regime’s radical ambitions in a growing axis of influence.

But it is in relation to Iran’s nuclear ambitions that recent events will be closely assessed. Despite the umpteen but so far futile efforts, the possibility of the world’s most volatile region becoming flooded with the world’s most dangerous weapon is still a real possibility, a point that will be hammered home to friend and foe of Tehran by the recent International Atomic Energy Agency report that suggests Iran has enough low-enriched uranium to produce one atomic bomb.

Irrespective of whether it was Mousavi or Ahmadinejad who won the election, compromise over Iranian nuclear ambitions, a matter of national pride and prestige, was never up for discussion. All factions within the regime uphold the country’s right to nuclear capability: it cements its status as a major power in the region, acts as a deterrent against forceful regime change and secures the theocracy.

It may indeed seem impossibly ambitious to try and resolve the nuclear issue through peaceful engagement with a hardline and complex regime; but theocratic Iran has always been hard-line and complex. The US may therefore build on its pre-election position and continue with the negotiating initiative of the P5+1, while supplementing it with continued attempts at rapprochement. It will find no reason to depart from this position, yet.

For the state that fears a nuclear armed Iran more than any other, time is running out. For Israel, continued intransigence by a radical, expansionist and potentially unelected government in Tehran requires urgent and decisive action. With every moment wasted, the chances of armed action against Tehran increases and particularly as we head closer toward the end of the so-called ‘timetable’ – rather than deadline – at the end of the year when the US will reassess its peaceful approach towards the issue.

For now, the immediate concerns for the international community are the internal divisions and the ongoing instability within Iran. An unstable and divided Iran is an unpredictable Iran that cannot be properly negotiated with.

It is still possible that the change so desperately sought by those within and outside of Iran may be achieved by the powerful wave of discontent created by the energetic and resolute army of protesters. Armed with the internet, their movement has moved on from domestic divisions to evolve into an enduring, defiant conquest for greater democracy, increased civil and women’s rights and interaction with the global community. Choosing oppression and isolation over concession and engagement may no longer be a choice for the Islamic republic.