AGE: Perhaps 33
OCCUPATION: Radical Shi'ite cleric, chief of the Mahdi Army in Iraq
NUMBER OF TIME COVERS: 1 [His face is on a poster held up by protesters in Iraq]
PREVIOUS APPEARANCES ON THE TIME 100: 1
PRO: Virulently anti-American cleric who controls an influential bloc of Iraq's Parliament and one of the country's most powerful private militias. He remains hugely popular with the nation's poorest Shi'ites, and has close ties to its influential neighbor, Iran.
CON: It is becoming increasingly clear that al-Sadr does not have full control over the Mahdi Army, and rivals are gunning for control of his forces and sources of revenue.
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