Gallagher has served operational tours in various fighter squadrons and carrier air wings. He commanded Fighter Squadron 142 spanning Operations Desert Shield and Desert Storm. He has commanded the Navy Fighter Weapons School "TOPGUN," USS Inchon and USS John C. Stennis where he became an honorary master chief petty officer. He also commanded Carrier Group 4 which was re-designated Commander, Carrier Strike Force Training Atlantic.
Gallagher served with the North Atlantic Treaty Organization (NATO) as the Deputy Assistant Chief of Staff for Policy while attached to Supreme Allied Commander Atlantic. He then led Concept Development and Experimentation for the newly formed Allied Command Transformation. This was followed by a tour as the Headquarters U.S. European Command’s Director of the European Plans and Operations Center (J-3), and prior to assuming his current duty as U.S. MILREP to the NATO Committee, he served as the Deputy Commander, U.S. European Command located in Stuttgart, Germany.
Gallagher has logged over 4,000 flight hours and 800 aircraft carrier landings from a variety of aircraft. Since earning his wings he has flown the: F-4, F-14, FA-18, and F-16N.
Gallagher’s decorations include the Defense Distinguished Service Medal, Defense Superior Service Medal (two awards), Legion of Merit (four awards), Meritorious Service Medal (two awards), Navy and Marine Corps Commendation Medal (two awards), NATO Meritorious Service Medal and various service decorations.