The end of Iran’s Islamic Republic

At this point, it is only the short-term future of Iran's clerical regime that remains in doubt. The current protests can be repressed, but the unelected institutions of priestly rule have been fatally undermined, and in the meantime, the Tehran government may be largely paralysed anyway. Each of these things has its own dynamic and timetable, but this is not a regime that can last many more years.

When it comes to repression, the Islamic Republic has a spectrum of security instruments that can be used synergistically: the regular national police for routine crowd control without much use of force; riot police units with batons that can beat up some demonstrators to discourage others; the much more brutal, under-class Basij militiamen who enjoy hitting and even shooting more affluent Iranians; and finally the not-incompetent technical arm of the regime which blocks cellular service to disrupt demonstrations, disrupts internet services and intercepts opposition communications.

Mousavi rejects the orders of Supreme Leader Khamenei, who must be obeyedIf violence were to escalate very greatly, Pasdaran revolutionary guard troops with their wheeled armoured vehicles might also be called in - at some risk to the regime, given that one unhappy losing presidential candidate, Mohsen Rezaee, was their long-term commander, though he left 12 years ago. The alternative of calling in the regular army with its tanks would be much more risky: the loyalty of the generals is unknown.

What has undermined the very structure of the Islamic Republic is the fracturing of its ruling elite. It was the unity established by its founder Ayatollah Khomeini that allowed the regime to dominate the population for almost 30 years, and it has now been lost. The very people who did much to create the institutions of priestly rule are now destroying their authority.

Mahmoud Ahmadinejad's leading rival for the presidency, Mir Hossein Mousavi, was prime minister from 1981 to 1989 when the Islamic Republic acquired its administrative structure, including its unelected head, the Supreme Leader, who commands all and must be obeyed in all things. But Mousavi now flatly rejects the orders of Supreme Leader Ali Khamenei to accept Ahmadinejad's re-election.

In this, Mousavi is joined by another losing candidate, former Speaker of the Majlis (parliament) and pillar of the establishment Mehdi Karroubi, and a yet more senior founder of the Islamic Republic, Ayatollah Ali Akbar Hashemi Rafsanjani. President from 1989 to 1997, among other things Rafsanjani is the chairman of the Assembly of Experts, whose 86 members choose the Supreme Leader and can ostensibly remove him.

During the campaign, Ahmadinejad accused Rafsanjani and his children of corruption in the harshest terms on live television. If Ahmadinejad's re-election is to be "definitive" and even "divine" as the Supreme Leader has declared, Rafsanjani would have to resign from all his offices, and his children would have to leave Iran. Instead he is reportedly trying to recruit a majority of the Assembly of Experts to remove Khamenei, or at least force him to order new elections.

The other key undemocratic institution that makes the Islamic Republic what it is - and that Mousavi and Rafsanjani among others helped to create - is the 12-member Guardian Council that can veto any laws passed by the Majlis, and has the power to reject any candidate who presents himself for election (only Islamists qualify). In recent years, it has persistently sided with the extremists and Ahmadinejad, using its veto powers very aggressively.

Supreme Leader Khamenei logically chose the Guardian Council to deal with the election dispute. The council announced that it might recount 10 per cent of the