He served as homeland security adviser to the White House for a year and then became head of the Department of Homeland Security when it was created.
A Vietnam War veteran - he was drafted into the army while at law school - and a close friend of the president, Mr Ridge was described by Mr Bush as "the right man for this new and great responsibility".
Mr Ridge is responsible for developing strategies to stop terrorist attacks in the US as well as creating a unified department assembled from parts of 22 agencies.
The department is in charge of border protection, such as the Coast Guard, Customs, the Immigration and Naturalization Service and the Transportation Security Administration.
It collects information on terrorist threats from the Central Intelligence Agency and the Federal Bureau of Investigation, which remain separate agencies.
Mr Ridge stepped down as governor of Pennsylvania to take up the homeland security job.
He said he felt personally involved in the 11 September attacks, because Flight 93 - apparently headed for the White House - was brought down in his state.
Valour award
Mr Ridge was born in Pittsburgh in 1945 and grew up in Erie in the west of Pennsylvania.
LIFE IN DATES
Mr Ridge then proceeded to law school, but was drafted at the end of his first year and sent to Vietnam in the spring of 1970.
During his time in Vietnam, Mr Ridge received the Bronze Star for valour.
In 1982, Mr Ridge was elected to Congress, where he served for 12 years.
He was elected governor of Pennsylvania in 1994 and re-elected in 1998.
As governor, Mr Ridge brought about a special legislative session on crime that led to the three-strikes law and a faster death penalty process.
However, he refused to follow the Roman Catholic Church's doctrine on abortion, supporting a limited form of abortion rights.
Running mate
Mr Ridge and Mr Bush became friends when Mr Ridge volunteered to help with the 1988 campaign for Mr Bush's father, former President George HW Bush.
Mr Ridge was mentioned as a potential running mate for George W Bush in his first election campaign in 2000.
When Mr Bush finally announced that Dick Cheney would be his vice-presidential candidate, Mr Ridge revealed that he had withdrawn his name three weeks earlier.
Mr Ridge and his wife Michele have two adopted children - Lesley and Tommy.
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©