A Surface Warfare Officer, he served at all levels of leadership and command in guided missile destroyers and cruisers. During the course of his career, Gehman had five sea commands in ranks from Lieutenant to Rear Admiral.
Gehman served in Vietnam as Officer in Charge of a Swift patrol boat and later in Chu Lai as Officer in Charge of a detachment of six swift boats and their crews. He subsequently served as executive officer of USS Mitscher from March 1971 to February 1973.[2]
His staff assignments were both afloat on a Carrier Battle Group staff and ashore on a fleet commander's staff, a Unified Commander's staff and in Washington, D.C. on the staff of the Chief of Naval Operations (four tours).
Promoted to four-star Admiral in 1996, he became the 29th Vice Chief of Naval Operations in September 1996. As Vice Chief of Naval Operations he was a member of the Joint Chiefs of Staff, formulated the Navy's $70 billion budget and developed and implemented policies governing the 375,000 people in the Navy.
Assigned in September 1997 as Supreme Allied Commander, Atlantic and Commander-in-Chief, United States Atlantic Command (later changed to Joint Forces Command), he became one of NATO's two military commanders and assumed command of all forces of all four services in the continental United States and became responsible for the provision of ready forces to the other Unified Commanders in Chief and for the development of new joint doctrine, training and requirements.
^ ab"Nominations Before the Senate Armed Services Committee, First Session, 105th Congress: Hearings Before the Committee on Armed Services, United States Senate". Vol. 105, no. 371. Washington, D.C.: U.S. Government Printing Office. 1998. pp. 527–529. ISBN978-0-16-056255-6.
