Early results of a pilot to test 100 percent scanning of U.S.-bound containerized cargo shows both promise and challenges, a top Department of Homeland Security official told lawmakers recently. Stewart Baker, assistant secretary of Homeland Security for policy, indicated there were many challenges to the goal of 100 percent scanning in every port but that the department will pursue that goal aggressively. The Sept. 11 commission recommendation law mandates the scanning of all U.S.-bound cargo containers at foreign ports by July 2012. The law gives the Homeland Security secretary leeway if he finds the available integrated scanning technology, which includes a combination of imaging — such as X-ray — and radiation detection, is not adequate.