Final answer:
The Department of Homeland Security was established post-9/11 to centralize and coordinate national security efforts. The Patriot Act was introduced to enhance federal surveillance and counterterrorism measures.
Step-by-step explanation:
After September 11, 2001, the Department of Homeland Security was established to provide a framework that provides a comprehensive national approach, applicable at all jurisdictional levels and across functional disciplines. The devastating terror attacks exposed a significant lack of coordination among various governmental agencies, which led to an overhaul of the national security apparatus with an emphasis on integration and communication to better address both international and domestic threats. As part of this response, the U.S. government, under President George W. Bush, pushed for the passage of The Patriot Act, expanding federal powers to monitor and prevent terrorist activities, which included enhanced surveillance capabilities without a warrant.