The first known account of the MACOs (Military Assistance Command Operations) was in the year 2153 when Captain Jonathan Archer of the NX-01 requested the services of security forces for his mission to the Delphic Expanse. Major J. Hayes commanded the MACOs that came aboard. Before that, the MACOs were a United Earth Military organization in service on Earth during the 2150’s prior to the founding of the Federation. The MACOs at that time were not associated with Starfleet.
Several MACO missions on the USS Enterprise are as follows:
September 2153 –Captain Archer and Commander Tucker were rescued from a Trellium mining planet.
October 2153 – Provided escort for Enterprise officers on the Xindi-Arboreal colony.
December 2153 – Provided combat training for the Enterprise officers.
May 2154 – Fend off an Augment boarding party.
November 2154 – Escort and guard of a Tellarite delegation.
2161 – Ambush of kidnappers on Regel X just prior to the formal treaty signing that created the United Federation of Planets.
There are no historical references to the MACOs after 2161.It seems entirely possible that the MACOs continued to operate as a separate organization from the Starfleet Navy and that Colonel West, at the Khitomere Conference in 2293 could have very well been a member of the MACOs. However, this has not been substantiated.
Much in the same way as Captain Archer asked for security forces, Captain Savander of the USS Tiberius asked Colonel Jackson to set up a squad of Marine Special Operations forces aboard the USS Tiberius to supplement the ships’ internal security forces. He needed some troopers that were trained in planet side activities and were able to take care of business. Colonel Jackson decided to operate these troops from the 631st Marine Strike Group already assigned to the USS Tiberius. However, they needed their own identity. Colonel Jackson had a distant relative that served in the 31st Marine Expeditionary Force (MEU) that was activated on March 1, 1967 as a Special Landing Force Alpha for operations in Vietnam. In honor of this relative and his unit, he decided to call the security forces the 31st MACOs. In addition, there is not any historical data in any database that substantiated that any MACO unit or units were still active in Starfleet or any other military organization outside of Starfleet. As this would be a Marine Special Operations unit, he changed the designation Military to Marine, Assistance to Assault and Command to Combat to more appropriately identify the squad.
Aboard the USS Tiberius, MACO now stands for Marine Assault Combat Operations. Also he chose to use the “Death’s Head” as seen on the ISS Enterprise alternate universe episodes, with a few changes on the MACO patch instead of the MACO shark that was used on the previous MACO unit’s patch aboard the USS Enterprise. This would give the squad a new identity. Starfleet Special Operations Command contacted the USS Tiberius to inquire if the Marine Special Operations teams would be interested in assisting in Force Recon missions. The answer was affirmative. This Force Recon teams will operate under the authority of the Marine Special Operations and Starfleet Special Operations Command. SFSO has nine (9) training courses that would have to be completed to qualify for the Force two Recon teams.