It will take a while to piece all of the evidence together, but what happened in Iran has all the markings of a coup. I don't know if the mullahs reacted against the masses of people demonstrating in the streets this week, or if this whole election was a sham to uproot and eliminate dissenters. Or perhaps they simply panicked, and overreached. This could backfire for Iran's rulers, both in the short- and long-term.
Gary Sick takes you through the timeline leading to where we are now.
Also, it appears that the government has arrested Mousavi, Karroubi, Karbaschi, and Khatami's brother. Thanks to Andrew Sullivan, who's keeping up to date on everything.