ABC News: Iraq Troop Surge Begins

Under the new plan, the city of Baghdad will be divided into nine separate sections at the request of Iraqis who want one Army and police battalion devoted to section.

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In a switch from the current course of action, these U.S. forces will be housed in the very neighborhoods they patrol. Military planners tell ABC News there will eventually be about 30 mini-bases, called joint security stations, scattered around Baghdad housing both U.S. and Iraqi troops.