After the September 11, 2001, attacks, Congress swiftly passes an antiterrorism measure called the U.S.A. Patriot Act “to enable capture of the individuals responsible for the 9/11 attacks, and to prevent future attacks.” Among its provisions is a dramatic expansion of the federal government’s authority to monitor suspected terrorists’ communications (including those made by e-mail and telephone) and to obtain online records, such as organization membership lists, individuals’ purchases and other transactions. Civil liberties advocates voice concern that the measure will infringe on citizens’ rights.