John Nagl

John Nagl
Left to right, Peter Bergen, John Nagl and Daniel R. Green, discussing Nagl's new book, Knife Fights: A Memoir of Modern War in Theory and Practice, at the New America Foundation, 27 October 2014
Born	1966 (age 50–51) Omaha, Nebraska
Allegiance	United States
Service/branch	United States Army
Years of service	1988–2008
Rank	Lieutenant Colonel
Unit	1st Cavalry Division 1st Armored Division 24th Infantry Division 34th Armor Regiment
Commands held	1st Battalion, 34th Armor Regiment
Battles/wars	Operation Desert Storm Operation Iraqi Freedom
Awards	Bronze Star Medal

John A. Nagl (born 1966) is a retired Lieutenant Colonel in the United States Army. He is former president of the Center for a New American Security and current headmaster of The Haverford School. Nagl is an expert in counterinsurgency and has published two books on military strategy.

Nagl was raised in Omaha, Nebraska, where he graduated from Creighton Preparatory School in 1984. He then attended the United States Military Academy at West Point, where he studied international relations and graduated near the top of his class in 1988. As a newly commissioned second lieutenant, he was chosen as a Rhodes Scholar and studied international relations at St John's College, Oxford, earning his MPhil in 1990.

Entering the Armor Branch of the US Army, Nagl led a tank platoon in the 1st Cavalry Division during the Gulf War. After returning from the Middle East, he commanded A Troop of the 1st Squadron, 1st Cavalry Regiment in the 1st Armored Division in Büdingen, Germany and served as Deputy Chief of Staff for Operations and Plans for the 24th Infantry Division at Fort Riley, Kansas.