Cooling's primary Military Operational Specialty (MOS) was as an infantry officer (0302) until his promotion to Colonel, when he was assigned an 8041, Colonel, Ground MOS. He received his 8003, General Officer MOS upon being promoted to his current rank. His first assignment as an infantry officer was with Second Battalion, Fourth Marines where he commanded rifle, weapons, and anti-armor platoons. Subsequently, he has commanded infantry and light armored reconnaissance units to the battalion level as well as the Marine Corps Mountain Warfare Training Center in Bridgeport, CA. He commanded Third Battalion, Third Marines during combat deployments to both Afghanistan during Operation Enduring Freedom and Iraq during Operation Iraqi Freedom 5. During 3/3's Afghan tour, the battalion deployed to Regional Command-East, which included the restive Kunar Province. Operations included ones in and around the Korangal Valley, including Operations Celtics and Spurs. Notably, 3/3 forced the surrender of a key regional high value target, a man named "Najmudeen," who dwelled in the Korangal Valley and was responsible for significant anti-coalition militia activity. Cooling, along with the battalion's operations officer and intelligence officer, and others, developed Operation Stars, which would be passed to their sister battalion, the 2nd Battalion of the 3rd Marine Regiment when 2/3 relieved 3/3 in the spring of 2005. The "shell" of Operation Stars that 3/3 developed would be renamed Operation Red Wings and changed considerably. Operation Stars was to be a conventional forces-centric operation. Red Wings became a special operations forces-centric operation for the opening phases.