The world can only watch as Iran implodes from within

The power struggle inside Iran is not driven by relations with the West, nor will its outcome necessarily change Tehran's strategic consensus. Rather, it's business as usual as the regime in Tehran implodes.

Two years after the disputed reelection of the Iranian president, Mahmoud Ahmadinejad, the Tehran streets that seethed with protest for months are quiet. But the silence belies the increasingly chaotic and rowdy struggle for control within the corridors of power - a contest in which those Iranians who risked their lives to protest two years ago have no clear favourite.

The key political contest today pits Ayatollah Ali Khamenei against Mr Ahmadinejad, the president behind whom (at great risk to the prestige of his office) the supreme leader threw his weight two years ago. The struggle has raged in the open for months, and it's far from certain that Mr Ahmadinejad will get to finish his current term of office.

The president, believing that Ayatollah Khamenei had become dependent on him after the 2009 election debacle, began to steadily and directly challenge the authority of the clergy the moment he returned to office.

Mr Ahmadinejad and his closest allies alarmed the clerics by seeking to refashion the state's ideology on nationalist - rather than Islamist - lines, and to shift its centre of political power from the clergy to the presidency.

The clerics are also outraged by Mr Ahmadinejad's religious populism. Appealing to a less educated poorer population, he claims a direct connection with Shiism's hidden 12th Imam, the messianic Mahdi, and as such claims that he doesn't need clerical supervision to govern on Islamic principles.

In April, when the president fired a pro-Khamenei intelligence minister, the supreme leader saw an opportunity to put Mr Ahmadinejad in his place, and remind him that his authority as president is no greater than that of his hapless reformist predecessor, Mohammed Khatami.

So Ayatollah Khamenei reinstated the fired minister, prompting Mr Ahmadinejad to stay away from work for 11 days - in unprecedented public defiance of the supreme leader's authority. The president was forced to retreat as more and more power centres, including from the Revolutionary Guards, lined up behind the ayatollah.

A torrent of public attacks on Mr Ahmadinejad and his allies followed, with the president's key aide and preferred successor, Esfandiar Rahim Mashaei, being arrested and charged with using "sorcery" in pursuit of his political agenda. And the head of Revolutionary Guards warned that "deviations" driven by "djinns, fairies and demons" would not be tolerated.

Thus was the climate in which Mr Ahmadinejad found himself being booed after his speech on the June 4 anniversary of the death of the revolution's founder, Ayatollah Ruhollah Khomeini.

Parliament, meanwhile, controlled by Mr Ahmadinejad's conservative rivals, is looking to press criminal charges for his attempts to take over the oil ministry. Ayatollah Khamenei is believed to want the president to finish his term, but in a humbled lame duck capacity.

While some reformists are happy to see the supreme leader turn on Mr Ahmadinejad, the ayatollah remains hostile to reform and has given them little reason to hope for better days even if he manages to bring the president to heel.

The same goes for Western powers. The Washington Post's David Ignatius suggested recently that the split was a result of Mr Ahmadinejad's camp reaching out for a nuclear deal with the US, implying that America needed the Iran president to prevail. Others, such as Washington-based analyst Geneive Abdo, argue the opposite - that Ayatollah Khamenei, despite his hostility, is preferable because he is averse to confrontation.

But the power struggle is not driven by relations with the West, nor will its outcome necessarily change Tehran's strategic consensus. Iran analysts Trita Parsi and Reza Marashi recently noted that Tehran sees the Arab Spring as weakening its US and Saudi rivals, which reinforces their aversion to a deal at this time.

"Iranian government reluctance to negotiate with America has not necessarily been rooted in an ideological opposition to the idea of talking or improving relations with Washington," they argue. "Instead, hard-liners in Tehran fear that any relationship with the US would require Iranian acquiescence to (a) status quo" that they believe is growing steadily weaker.

That leaves Western powers facing a major problem - at least to the extent that their Iran focus remains centred on its nuclear programme. There's little reason to expect Tehran to change course on matters of national security any time soon. Still, despite Iran's defiance on uranium enrichment, the assessment of the US intelligence community remains that Iran is not currently building nuclear weapons, and has taken no decision to do so.

"We do not know, however, if Iran will eventually decide to build nuclear weapons," the US director of national intelligence, General James Clapper, reported in February. "Iran's nuclear decision-making is guided by a cost-benefit approach, which offers the international community opportunities to influence Tehran."

In the coming weeks, we can expect the drumbeat of pressure to intensify, as the Obama administration looks to press for new sanctions. It will grow even louder if the Republicans make an election issue out of Iran's continued defiance.

Investigative reporter Seymour Hersh recently wrote that senior intelligence sources tell him of a "discrepancy between the available intelligence and what many in the White House and Congress believe to be true" about Iran's nuclear activities. And Israel's recently retired Mossad chief, Meir Dagan, publicly castigated the Iran hysteria being cultivated by the Netanyahu government, warning that it was creating panic and fuelling consideration of military action against Iran.

Mr Dagan said he's not expecting Israeli military action in the next two years. Nor is Iran likely to bow to Western demands in that time. It's business as usual, then, even as the regime in Tehran implodes.

Tony Karon is an analyst based in New York. Follow him on Twitter @TonyKaron