The Strategy Page is worth a look. The Belmont Club has some very interesting comments on this paragraph:

"U.S. troops maintain databases of who they are fighting, the better to pick targets for raids or surveillance. ... Daily, the smart bombs blow apart houses used by the gangs for housing, headquarters or ammo dumps. The gangs have become very paranoid, believing there are spies everywhere. They are correct, but some of the most revealing spies are unreachable. Above Fallujah, U.S. warplanes and UAVs circle constantly, able to clearly view what is below, day or night. The telescopic bomb sights allow pilots to see what kind of weapon people are carrying, or whether women and children are in a crowd. The gangs have learned to never gather in large groups, at least not without plenty of women and children nearby for protection. But that doesn’t always work, for the AC-130 gunships can kill a man without harming someone ten feet away. The gangs fear that the American troops are coming back to Fallujah, and they are right. The not-so-secret plan is to go back in before the end of the year, kill all gang members that can be found, and then turn the city over to Iraqi troops, composed mostly of Shia and Kurds."