U.S.-hired contractors rely on laborers from impoverished countries, but no one looks out for the rights -- or lives -- of the foreigners...Contractors working for the United States, including KBR [Kellogg Brown & Root], a Houston-based subsidiary of Halliburton Corp., have brought tens of thousands of workers into Iraq from impoverished countries... In relying on [this] workforce..., the U.S. has embraced a system of labor migration rife with abuse, corruption and exploitation, according to dozens of contractors, migrant workers, labor officials and advocates interviewed in four countries... KBR...says all its subcontractors are required to respect local labor laws and provide appropriate housing, medical treatment and security protection for workers. [also refers to Moonlight Manpower, Morning Star, Daoud & Partners, Besharat & Partners]