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3d Marine Division


3d Marine Division

The Fighting Third

Okinawa, Japan
Lieutenant Colonel Sean W. Barnes Commanding Officer 3d Reconnaissance Battalion

LtCol Barnes was commissioned via the Officer Candidate Course program in April 2000.  He holds a Bachelor of Science degree in Criminal Justice from Northeastern University in Boston.   

In January 2001, LtCol Barnes was assigned to 3d Battalion, 4th Marines in Twenty-Nine Palms, California. He served as a Rifle Platoon Commander, Weapons Platoon Commander and Company Executive Officer.  During this time, he deployed to Okinawa, Japan in support of the Unit Deployment Program, OPERATION IRAQI FREEDOM I and II, including OPERATION VIGILANT RESOVLE. 

In 2005, LtCol Barnes reported to 3D Reconnaissance Battalion, Okinawa, Japan where he served as the Amphibious Reconnaissance Platoon Commander deployed to the 31st Marine Expeditionary Unit (MEU).  In 2006, Captain Barnes led 3d Reconnaissance Battalion’s Provisional Rifle Platoon during deployment to OIF.   

LtCol Barnes attended resident Expeditionary Warfare School in 2008.  Upon graduation, he reported to 3D Battalion, 1st Marines where he served as Battalion Landing Team 3/1 Assistant Operations Officer deployed to the 31st MEU. In December 2008, LtCol Barnes took command of Kilo Company, and in 2010 deployed in support of OPERATION ENDURING FREEDOM. 

July of 2011, LtCol Barnes reported to Marine Corps Base Hawaii for duty as Inspector-Instructor, Detachment, 4th Force Reconnaissance Company and 2nd and 3d Platoons, Company F, Anti-Terrorism Battalion.

From July 2013 to January 2015, LtCol Barnes served as the Battalion Executive Officer 1st Battalion, 3d Marines where he deployed again to Okinawa, Japan in support of the Unit Deployment Program. 

From January 2015 to June 2015, LtCol Barnes served in the 3D Marine Regiment Future Operations section where he was lead planner for EXERCISE BALIKATAN 2015. 

From July 2015 to June 2018 LtCol Barnes was assigned as Reconnaissance Advocate, Headquarters Marine Corps, Plans, Policies, and Operations.  During this time, LtCol Barnes deployed in support of OPERATION INHERENT RESOVLE, serving as Deputy to the Commanding General of Operations-Baghdad.

LtCol Barnes is a graduate of the Infantry Officers Course, Mountain Leader Course (Summer), Amphibious Reconnaissance School, SERE, Marine Combatant Dive School, Airborne School, Multi-Mission Parachute Course, High Risk Personnel, Expeditionary Warfare School, and Command and Staff.   

His personal decorations include the Bronze Star, Defense Meritorious Service Medal, Meritorious Service Medal, Navy and Marine Corps Commendation Medal with Combat Distinguishing Device, Navy and Marine Corps Achievement Medal with Combat Distinguishing Device, and Combat Action Ribbon.