According to this, "two critical lines...were crossed yesterday" in Iran.
...The first was widespread savagery and violence by the junta on the day of Ashura. This breaks a profound taboo, violates the integrity and core meaning of the religious festival, and places the regime symbolically as the enemy of Shia Islam. This has offended not just the urban elites but the pious poor and rural population.
The second was "
the calculated assassination of Ali Mousavi, the rightful president's nephew," which "
creates a martyr connected to the leader of the Green Movement, and provides a cycle of more mourning and potential for unrest." Not smart. In fact, it could be a fatal error by the Iranian theocratic dictatorship
according to this analysis.
Killing for any reason is forbidden on Ashura. So in addition to ten dead protesters, it is absolutely insane that Khamenei then assassinated Moussavi's nephew. Ali Moussavi was run over by a car and then shot in the street. Government officials confiscated his body to prevent a funeral.
Hundreds of people have been arrested, and at the end of this, dozens could be confirmed killed. Killing Moussavi's nephew on Ashura was probably one of the dumbest decisions the regime could've possibly made. Protesters have largely switched from chants against Ahmadinejad to chants against Khamenei himself. There is, of yet, no "revolutionary alternative" to the Supreme Leader, and he controls the military and the security forces, but basically he is fucked in the long term, and a lot of Iranian dissidents are about to be locked up and killed.
Remember, it was just such a cycle of violence and mourning that ultimately brought down the Shah of Iran in January 1979. Will history repeat itself in Iran 31 years later? It looks like we're about to find out.