John F. Lehman, Jr. (born September 14, 1942) is an American investment banker and writer who served as United States Secretary of the Navy in the Reagan administration and since 2003 has been a member of the 9/11 Commission.
Education and family
Born in Philadelphia, Pennsylvania, he graduated from La Salle College High School and received a B.S. in international relations from St. Joseph's University in 1964, gained a B.A. and M.A. from the University of Cambridge and went on to earn a Ph.D. from the University of Pennsylvania.
He is a first cousin, once removed of the late Grace Kelly (Princess Grace of Monaco), and is Chairman of the Princess Grace Foundation-USA, a public charity established after Princess Grace's death to support emerging artists in film, dance and theater. He led the American delegation to the funeral of Prince Rainier. 
Lehman served in the Air Force Reserves for three years while at Cambridge, then in 1968 left the Reserves and joined the United States Navy Reserve as an ensign, later rising to the rank of commander. He worked for UBS AG, then later was president of Abington Corporation, from 1977 to 1981, when he was appointed Secretary of the Navy. As the 65th Secretary, Lehman launched the idea of building a "600-ship Navy" and was unique in still serving as a Commander in the Naval Reserve while Secretary at the young age of forty. He developed a strategic concept to counter the threat of Soviet incursion into Western Europe known as the "Lehman Doctrine." The plan called for a military response to any Russian invasion in Europe by attacking and invading the Soviet Far East along the Pacific, a much less defended front. Forces would sever the trans Siberian railroad and fight westward toward Moscow. Lehman was important in the forced retirement of Admiral Hyman G. Rickover. Lehman resigned in 1987.
As of 2004, Lehman is chairman of the private equity investment firm J. F. Lehman and Company. He is also an honorary member of the First Troop Philadelphia City Cavalry, the oldest military unit in continuous service to the Republic of the United States. As of 2005, he is a member of a number of influential conservative American thinktanks, including the Project for the New American Century, the Heritage Foundation, the Foreign Policy Research Institute, the Center for Security Policy, and the Committee on the Present Danger. 
After his work in the 9/11 commission in 2002, there was increased speculation that Lehman might be named to a chief security post within the Bush administration. Positions suggested included CIA Director, Director of National Intelligence and Defense Secretary (if Donald Rumsfeld stepped down). As of 2006, none of this speculation has proved accurate. He currently serves as Chairman of the Princess Grace Foundation-USA and as a director of the OpSail Foundation. He is also a member of the Board of Overseers of the School of Engineering at the University of Pennsylvania, and is a trustee of La Salle College High School.  Additionally, Lehman is an Advisory Board member for the Partnership for a Secure America, a not-for-profit organisation dedicated to recreating the bipartisan center in American national security and foreign policy. 
- On Seas of Glory
- Command of the Seas
- Making War
- America the Vulnerable