The potential participation of the Marine Corps in SOCOM has been controversial since SOCOM was formed in 1986 . At the time , Marine Corps leaders felt that their Force Reconnaissance units were best kept in the Marine Corps ' MAGTF command structure , and that the detachment of an elite Marine Special Operations unit from the Marine Corps would be to the detriment of the Marine Corps as a whole . A re-evaluation following the September 11 attacks and the War on Terrorism , along with new policy established by Secretary Rumsfeld and then-Commandant Gen. James L. Jones at The Pentagon , caused the Marine Corps to work towards integration with SOCOM . The establishment of MARSOC represented the most significant step towards that goal , and followed the establishment of MCSOCOM Detachment One ( DET1 ) , a small Marine Corps detachment formed as a pilot program to test Marine Corps integration into SOCOM . It was made up of mostly Force Recon Marines from 1st and 2nd Force Reconnaissance Companies along with other hand-picked support men and served with Navy SEALs under Naval Special Warfare Group One . Detachment 1 conducted a multitude of special operations in Iraq alongside their Special Operations brothers of the sister services . SOCOM conducted a study of the unit 's deployment , which clearly indicated success and strong performance . Detachment 1 was disbanded in 2006 soon after the creation of MARSOC . The first of many Marine Special Operations Companies stood up in June 2006 . MARSOC 's initial deployment to Afghanistan in 2007 was mired in controversy when its Fox Company was sent back to the United States and its commander relieved from duty after a shooting incident . The incident that resulted in as many as 19 civilians killed involved a complex ambush by insurgents that included a suicide VBIED and small arms fire . Allegations later arose that the MARSOC operators killed the civilians while suppressing enemy fire , but these allegations proved false . MARSOC Marines also took part in Operation Enduring Freedom – Philippines
September 11 attacks
September 11 attacks
United States Marine Corps Forces Special Operations Command