Which federal agency is most closely associated with aviation security regulation?

The Transportation Security Administration (TSA) is the federal agency primarily responsible for ensuring the safety and security of the United States transportation systems, which includes aviation security regulation. Created in the wake of the September 11 attacks, the TSA's mandate includes the development and implementation of security measures for airports, airlines, and other transportation services. The agency oversees the screening of passengers and baggage to prevent threats to aviation security and works closely with airport authorities and airline carriers to establish protocols aimed at safeguarding air travel.

While the Federal Aviation Administration (FAA) plays a crucial role in regulating civil aviation, its focus is more on the safety of aircraft, flight operations, and air traffic management rather than directly overseeing security measures. The Department of Homeland Security (DHS) encompasses the TSA but has a broader focus on preventing and responding to domestic emergencies. The National Transportation Safety Board (NTSB) primarily investigates transportation accidents and incidents and is not directly involved in the regulation of aviation security. Thus, the TSA is the most directly tied to the regulatory framework governing aviation security.