This is a demonstration not of Moqtada al Sadr's strength, but of (a) the strength of Grand Ayatollah al Sistani, and (b) the power of religion in the contemporary Middle East.
Sadr grabs the headlines, but Sistani is the true wielder of influence. Sistani was supposed to issue a fatwa (probably already has) defining the duty of Iraqis to submit to the government's authority. He is against the 'occupation' but not by military means. Sadr's tack is to employ bellicose rhetoric and limited displays of force to keep the followers of the Sadr Trend (his father's movement, Moqtada does not have any serious influence as a cleric, only as a militia leader) fired up and supportive. Sistani as one of the four Grand Ayatollas comprising the Najaf Marja (supreme theological council) is far more influential and posits true Shiaism as 'quietist' not activist - viz a viz eschewing direct political involvment in state affairs.
While Sistani is against the presence of CF on Iraqi soil, he is also against clerics running the state (as in Iran) and against the wanton spillage of Iraqi blood. Sadr's stand down of JaM probably has more to do with his aspirations to become an Ayatollah (which requires submission to the current Marja) and less with political jockeying against the CF.
Bookmarks