Thursday is shaping up to be another huge day of demonstrations and counter-demonstrations in Iran, with pro- and anti-Ahmadinejad factions looking to demonstrate their ability to bring people into the streets for 22 Bahman, the anniversary of the founding of the Islamic Republic. Supreme Leader Ayatollah Ali Khamenei has called on the nation to "give all arrogant [Western] powers a punch in the mouth" by showing their support for the revolution and, presumably, him. The credibility of both sides is at stake.
Of course, the regime in Tehran is taking no chances -- arresting protest leaders, shutting down Gmail Wednesday, and restricting text-messaging services in the hopes of keeping the opposition from organizing and getting the word out. Already there are signs that reaching people within Iran is more difficult than usual. And Al Arabiya reports that foreign journalists -- many of whom are back in the country for the first time since last summer -- will be allowed to cover Ahmadinejad's speech only, and not the rallies themselves.
These are not the actions of a confident government.
And yet, there are still few reliable reports suggesting that the regime is fracturing. I've seen unsourced assertions saying so, as well as unverifiable accounts traced back to the National Resistance Council of Iran, a group dominated by the odious Mujahedin-e Khalq. (A great example of unduly credulous reporting is Richard Spencer describing the NCRI as an "umbrella opposition group in exile.") And key swing players like Ali Akbar Hashemi Rafsanjani haven't stuck their necks out too far to support the greens (more here).
Be on the lookout for real evidence that elements of the regime -- policemen, militia members, etc. -- are refusing to crack heads. My suspicion is that it's still too early for us to see that sort of fragmentation on a large scale; Iran's economy is going to need to get much worse before Ahmadinejad's lower-class base starts to turn on the regime in significant numbers. But I'm happy to be proven wrong.