The enigma of al-Sadr

al-Sadr is an enigma. Juan Cole reports that his team, which has been boycotting the Iraqi Parliament since al-Maliki met with Bush in Jordan, is returning to Parliament even though the government has arrested 400 of al-Sadr's militia. So, what's motivating the guy? I don't get it, but if it works towards stabilizing the Iraqi government and promotes reconciliation among the three warring camps, I'm for it.