Al-Sadr, Where is he? I don't know, I don't know...

Not Iraq! (cheers)

I think I can pierce the mystery:

1. Sadr is one of the bulwarks of PM Maliki of Iraq.
2. Maliki has been under pressure from Bush to man up and start dealing with all the militias.
3. Sadr leaves the country before the American and Iraqi army start to bring the pain.
4. The reason we didn't wack Sadr back in 2004 was because he had the protection of the Shi'ite religious establishment, whom we did not want to offend.

Conclusion: a deal was reached with the al-Sistani, the Iraqi Ayatollah, that we would be permitted to go after Sadr's army provided that Sadr himself was not harmed. Sadr conveniently blows town and lets his lieutenants take the fall. I wouldn't be at all surprised if he returns post-surge and remains a noisy, albeit non-paramilitary force in Iraq for decades to come.