** FILE ** A Miami Metro Police bomb squad truck passes by a cargo container as it enters the Port of Miami in Miami in this Jan. 7, 2007 file photo. To thwart a nuclear terrorist, the U.S. is requiring 100 percent screening of U.S.-bound ships at their more than 600 foreign starting points. The legislation passed in Congress sets a five-year deadline for having the system in place but, recognizing the technology might not be ready, gives the Homeland Security secretary the authority to extend that deadline by two-year increments. (AP Photo/Wilfredo Lee, File)