Domestic Surveillance Post-9/11

After the attacks on September 11, 2001, the United States implemented several significant policies and actions aimed at combating terrorism both domestically and internationally. One of these initiatives was the establishment of the Department of Homeland Security in 2003. This change aimed to consolidate numerous federal agencies to enhance coordination and response to terrorist threats.

Which of the following actions implemented by the U.S. government in response to the 9/11 attacks is most directly associated with increasing domestic surveillance of its citizens?