Sadr City is Moktada al-Sadr’s place, and the Americans have never come close to subduing it. There would not be an American forward outpost permanently stationed there, with patrols going out every day, if Mr. Sadr didn’t want it. The fact is that back in January, the whole thing was closely and specifically negotiated between the Americans, the Iraqi government and Mr. Sadr’s people.

Likewise, when Mr. Sadr withdrew all six ministers of his party from the cabinet in April, it was greeted by the press as a prelude to Iraq’s next great cataclysm. Few recalled that he had done more or less the same last fall, in protest at Prime Minister Nuri al-Maliki’s meeting in Jordan with President Bush. That gesture, greeted with similar alarmism, was followed two months later, as this one will be, by a return of the Sadrists to their posts.

Nor did most commentators note that even as he pulled out of the cabinet, Mr. Sadr was keeping his 30 members in Parliament, or that the ministries he was given sway over in the power-sharing agreement were still being run by their Sadrist appointees.

The Sadrists’ cooperation with their own government gets ever deeper. An Iraqi friend of mine in Baghdad recently tagged along with a Mahdi Army element on a mission to Baghdad’s Dora neighborhood, a particularly bloody place where the Mahdi Army used to play an active role in protecting Shiites from Sunni “cleansing.” My friend and the Sadrists drove to Dora at midnight, confirmed that the Iraqi Army was there and keeping the Shiite families safe, and went home.

There is also much concern in Washington and elsewhere that Mr. Sadr may be a pawn of the Iranians. This notion ignores the history of his movement and the essential nationalism underlying his project. By allying themselves with and speaking for the Shiite poor, Mr. Sadr and his father have long differentiated themselves from the traditional Shiite hierarchy in Najaf, with its great wealth and its ties to Iran.

The Sadrist movement has always been about Iraq for the Iraqis. They might accept help from Iran — and I saw Iranian supplies in their compounds in Najaf in 2004 — but the movement is not for sale. Mr. Sadr gets his strength from the street. And the Arabs of the Iraqi street have no time for Persian bosses.

Nor do they seem to want to foment an all-out civil war. For all the time I have spent with Sadrist death-squad leaders who focus on killing former Baathists and Al Qaeda’s supporters (Sunnis all), I have spent just as much time with Mahdi men who have been sent by their leaders to protect Sunni mosques after Sunni provocations, lest Shiites retaliate too broadly.