Entering Sadr City without a single shot fired

The AP has a pretty good article on the "major" US operation in Sadr City.

U.S. and Iraqi troops poured into Baghdad's main Shiite militia stronghold Sunday, encountering no resistance in the one-time Sadr City combat zones but testing the Shiites' commitment to the U.S.-promoted campaign to drive militants from the capital.....

The quiet but dramatic advance in Sadr City — involving nearly 1,200 U.S. and Iraqi forces who didn't fire a shot — marked one of the most significant developments in the security clampdown in Baghdad since it took effect nearly three weeks ago.

But it only received the green light after drawn-out talks between U.S. commanders and political allies of radical Shiite cleric Muqtada al-Sadr and his powerful Mahdi Army. Both sides are watching each other for any wrong moves on the same streets where they battled in the past, including intense urban warfare in 2004.

Makes "cooperation" me wonder about my thesis in the next post.