A recipient of two Purple Hearts while an infantry squad leader in the Vietnam War, Hagel returned home to start careers in business and politics. He co-founded Vanguard Cellular, the primary source of his personal wealth, and served as president of the McCarthy Group, an investment banking firm, and CEO of American Information Systems Inc., a computerized voting machine manufacturer. A member of the Republican Party, Hagel was first elected to the United States Senate in 1996. He was reelected in 2002, but did not run in 2008.
On January 7, 2013, President Barack Obama nominated Hagel to serve as Secretary of Defense. On February 12, 2013, the Senate Armed Services Committee approved Hagel's nomination by a vote of 14–11. On February 14, 2013, Senate Republicans denied Democrats the 60 votes needed to end the debate on Hagel's nomination and proceed to a final vote, citing the need for further review. It was the first time in U.S. history that a nominee for Secretary of Defense was filibustered, although candidates for other cabinet offices have been filibustered before. On February 26, 2013, the Senate voted for cloture on Hagel's nomination and confirmed him by a vote of 58–41. He took office on February 27, 2013, as his predecessor Leon Panetta stepped down.
Hagel previously served as a professor at the Edmund A. Walsh School of Foreign Service at Georgetown University, chairman of the Atlantic Council, and co-chairman of the President's Intelligence Advisory Board. Before his appointment as Secretary of Defense, Hagel served on a number of boards of directors, including that of Chevron Corporation.
On November 24, 2014, it was announced that Hagel would resign from the position of Secretary of Defense following conflicts within the administration, particularly relating to issues concerning ISIL.
Hagel was born in North Platte, Nebraska, a son of Charles Dean Hagel, and his wife Elizabeth (Betty) Dunn. His father was of German heritage, while his mother was of Irish and Polish ancestry. Growing up, Hagel lived across Nebraska; in Ainsworth, Rushville, Scottsbluff, Terrytown, York and Columbus, Nebraska. Hagel was the oldest of four brothers. His father, a veteran of World War II, died suddenly on Christmas morning, 1962, at the age of 39, when Hagel was 16. He graduated from St. Bonaventure High School (now Scotus Central Catholic High School) in Columbus, Nebraska, in 1964, the Brown Institute for Radio and Television in 1966, and he earned a BA degree in history at the University of Nebraska at Omaha in 1971.