Baghdad

AS THE SAYING GOES: Necessity is the mother of invention. For the U.S. soldiers keeping the peace and routing out insurgents in central Iraq, it’s often a lesson in improvisation and learning “on the job.” From patrolling the busy streets in search of information on the whereabouts of Saddam Hussein and his loyalists, to arresting looters and thieves, to house-to-house raids and prisoner snatches, U.S. troops here are conducting operations for which many were ill-prepared before they arrived here. And in some cases it seems that the units are in over their heads.