Det One

Marine Corps Special Operations Command Detachment One
Marine Corps Special Operations Command Detachment One insignia
Active20 June 2003–2006
Allegiance United States of America
Branch United States Marine Corps
TypeSpecial operations forces
RoleAir assault
Amphibious reconnaissance
Amphibious warfare
Anti-tank warfare
Artillery observer
Battlespace
Bomb disposal
CBRN defense
Clandestine operation
Close-quarters battle
Counter-sniper tactics
Counterterrorism
Desert warfare
Direct action
Forward air control
Hostage rescue
HUMINT
Intelligence assessment
Irregular warfare
Jungle warfare
Long-range penetration
Military intelligence
Mountain warfare
Naval boarding
Parachuting
Patrolling
Raiding
Reconnaissance
SIGINT
Special operations
Special reconnaissance
Tactical communications
Tracking
Urban warfare
Size86
Part ofUS Special Operations Command
Garrison/HQCamp Pendleton, California, US
EngagementsOperation Iraqi Freedom
Commanders
Colonel of
the Regiment
Robert J. Coates

The Marine Corps Special Operations Command Detachment One, also simply known as Det One, was a pilot marines special operations forces program of attaching a permanent unit of the United States Marine Corps (USMC) to the United States Special Operations Command (USSOCOM). It was commanded by Col. Robert J. Coates, former commanding officer of 1st Force Reconnaissance Company. Det One was activated on 19 June 2003 and had its headquarters at Camp Del Mar Boat Basin in Camp Pendleton, California. It was disbanded in 2006 and succeeded by the permanent United States Marine Corps Forces Special Operations Command (MARSOC).