The opposition movement that emerged after Iran’s presidential election last June has defied the government clampdown by using official events to organise mass demonstrations.
The latest round of demonstrations began on Students’ Day, 7 December. This marks the deaths of three students during protests against the 1953 coup that installed the Shah as dictator.
Thousands of students in Tehran, Kerman, Mashhad and other cities turned commemorative rallies into anti-government demonstrations. They clashed with security forces and student members of the pro-government Basij militia.
As student unrest spread to 17 universities across the country, the death of Grand Ayatollah Hussein Ali Montazeri on 19 December ignited wider protests.
He had become one of the leading figures of the opposition movement by criticising President Mahmoud Ahmadinejad and Supreme Leader Ali Khamenei.
His funeral in the city of Qom turned into a mass rally and was marked by skirmishes between mourners and security forces.
Bigger protests erupted on the seventh-day commemoration of his death, which coincided with the related Tasua and Ashura ceremonies on 26 and 27 December.
Ashura marks the death of the third Shia imam, Hussein. His small band of supporters fought against a repressive army in the seventh century.
Iran has a majority Shia population and by symbolising the fight against injustice, the festival is seen in Iran as a time to mobilise against tyranny.
In the run-up to these celebrations the opposition movement announced that it would take to the streets again. The government and conservative clerics warned that they would crush those who “exploit” religious ceremonies.
But hundreds of thousands Iranians defiantly took part in the Tasua and Ashura ceremonies.
Older people joined the youth on demonstrations in Tehran, Tabriz, Ardabil, Mahabad, Qom, Shiraz, Isfahan and Najaf Abad.
The government unleashed the Basij militia and plain clothes security forces.
More than 500 people were arrested and nine were killed, among them the nephew of opposition leader Mir Hussein Mousavi.
The government went on to widen the crackdown, arresting more activists and journalists.
It also attempted to rally support. A pro-government demonstration in Tehran drew tens of thousands, but it was dwarfed by the hundreds of thousands that the opposition has attracted.
However, unlike the hated regime of the Shah, which fell to a mass movement in 1979, the Islamic Republic still has a base of support, though it has been eroding rapidly in recent months.
Tensions are building up in the conservative camp. The alliance between President Ahmadinejad, Supreme Leader Khamenei and the Revolutionary Guard commanders is hardening, but becoming more isolated.
They still control the military, although they must be concerned that in the last weeks some of their troops have refused to shoot at demonstrators.
Internal tensions are increasing on the opposition side as well. The recent protests highlighted the radical spirit developing inside the movement.
Unlike six months ago, the slogans are not confined to elections. Many target the authority of Khamenei.
And, importantly, some protesters have started to fight back against the Basij and security forces, building barricades, throwing stones and even attacking police and Basij buildings.
This is already worrying the leadership of the movement around Mousavi, who would like to see a compromise with the conservative forces.
The key question for the movement now is whether it can move into the workplaces, turning the street protests into mass strikes, as happened in the revolution of 1979, and as we saw a glimpse of last summer.
Linking up with workers is vital if the protesters are to avoid brutal state repression—and transform their movement into one with the potential to make a revolution.