What major security responsibility was transferred from the FAA to TSA in 2001?

The major security responsibility that was transferred from the FAA to the TSA in 2001 is civil aviation security. This transition took place in response to the events of September 11, 2001, which highlighted significant vulnerabilities in the aviation security system. The TSA was created as part of the Homeland Security Act to centralize and enhance security measures across all forms of transportation, including commercial air travel.

This change aimed to ensure a more coordinated and robust approach to protecting the nation's transportation systems, particularly focusing on the prevention of unauthorized access to aircraft and airports, the screening of passengers and their belongings, and the development of new security protocols. The movement of civil aviation security oversight to the TSA allowed for a more unified and focused effort in securing air travel from terrorism and other threats.

Airport construction approvals, management of commercial air traffic, and aircraft maintenance regulations remain under the purview of the FAA, ensuring that the safety and reliability of the aviation infrastructure are adequately managed while security is handled by the TSA.