The Transportation Security Administration (TSA) was created in the aftermath of 9/11. On November 19, 2001, the Aviation and Transportation Security Act (ATSA) was signed into law, which among other things established TSA within the Department of Transportation.
TSA was later moved to the Department of Homeland Security (DHS) when the federal government restructured to accommodate DHS’s transition into a cabinet level agency. TSA was placed on the Border and Transportation Security directorate, which brought the major border security and transportation operations under one roof. TSA protects the nation’s transportation systems to ensure freedom of movement for people and commerce.