Thomas Joseph "Tom" Ridge (born August 26, 1945) is an American politician who served as a member of the United States House of Representatives (1983–1995), the 43rd Governor of Pennsylvania (1995–2001), Assistant to the President for Homeland Security (2001–2003), and the first United States Secretary of Homeland Security (2003–2005). Since re-entering the private sector, Ridge has served on the boards of The Home Depot, The Hershey Company and Exelon Corporation and as a senior advisor to Deloitte & Touche, and TechRadium. Ridge is also the founder and CEO of Ridge Global, LLC, a Washington, D.C. based security consulting firm. Ridge spent time campaigning with Senator John McCain during his 2008 bid for the presidency and was believed by some to have been in the short list of potential running mates.

Ridge was born in Munhall, Pennsylvania, in Pittsburgh's Steel Valley, the oldest of three children. His parents were Laura (née Sudimack) and Thomas Regis Ridge, who was a traveling salesman and Navy veteran. Ridge's maternal grandparents were Carpatho-Rusyn immigrants from the former Czechoslovakia (now Slovakia), and his paternal great-grandparents emigrated from Great Britain. Ridge was raised in veterans' public housing in Erie, Pennsylvania. He was educated at St. Andrews Elementary School and Cathedral Preparatory School and did well both academically and in sports. He earned a scholarship to Harvard College, where he paid his way through with construction work, played intramural baseball and football, and graduated with honors in 1967.

After his first year at the Dickinson School of Law, he was drafted into the United States Army, where he served as an infantry staff sergeant in the 23rd Infantry Division during the Vietnam War. He earned the Bronze Star, National Defense Service Medal, Vietnam Service Medal, Vietnam Campaign Medal, Vietnam Gallantry Cross Unit Citation with Palm, and the Combat Infantryman Badge. Later, he was offered a commission as an officer but turned it down when he learned that it would require an extra year of service.