The globalization of the world economy has led to an increasingly important role of international transportation and supply chain management. In particular, container transportation and maritime trade are important parts of international transportation as about 90 percent of the world's cargo moves by container. Each year, about 16 million containers enter seaport container terminals in the United States. After September 11, 2001, special attention has been given to the vulnerability of container transportation to terrorist activities. This fact has made it impossible for the United States to ignore potential terrorists' dangers and threats and the potential use of dangerous goods such as nuclear and radiological weapons at seaport container terminals.