http://www.rand.org/blog/2012/07/revisiting-100-percent-inspection.html

Last week in a New York Times op-ed, Congressmen Jerrold L. Nadler, Edward J. Markey, and Bennie G. Thompson made a plea for the Obama administration to fully implement the Secure Freight Initiative to comply with Section 232 of the Safe Ports Act of 2006. This provision in the law mandates that 100 percent of cargo containers shipped from overseas to U.S. ports be scanned using noninvasive imaging (e.g., x-ray machines) and radiation detection equipment. Since its passage, this requirement has been among the most highly politicized and poorly understood provisions of homeland security law.

Like the congressmen, advocates of 100 percent inspection of U.S.-bound containers paint a picture of a looming catastrophe. My early analysis of securing the global supply chain described how the system's vastness both drives the global economy and makes it an attractive way to move illicit materials.