The Direct Air Support Center (DASC) is the principal United States Marine Corps aviation command and control system and the air control agency responsible for the direction of air operations directly supporting ground forces. It functions in a decentralized mode of operation, but is directly supervised by the Marine Tactical Air Command Center (TACC) or the Navy Tactical Air Control Center (NTACC). During amphibious or expeditionary operations, the DASC is normally the first Marine Air Command and Control System (MACCS) agency ashore and is usually categorized as the Ground Combat Element's (GCE's) senior Fire Support Coordination Center (FSCC). The DASC's parent unit is the Marine Air Support Squadron (MASS) of the Marine Air Control Group (MACG).

The Battle of Chosin Reservoir, also known as the Chosin Reservoir Campaign or the Battle of Lake Changjin, was an important battle in the Korean War. The name "Chosin" is derived from the Japanese pronunciation "Chōshin", instead of the Korean pronunciation.