Det One
military unit
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).
Personnel
The unit consisted of 81 Marines and 5 Navy Corpsmen divided among 4 sections:
reconnaissance element (30 men)
Marine Corps Intelligence element (29 men), containing a headquarters element and
a Radio Reconnaissance Team (RRT), (9 men)
a SIGINT support team (3 men)
a human intelligence (HUMINT) exploitation team (HET), (6 men)
an all-source fusion team (12 men)
fires element (7 men)
headquarters element
The original Marines that formed the detachment were hand-picked from over 500 superior candidates. Despite common misconceptions, Det One was not a beefed-up United States Marine Corps Force Reconnaissance (FORECON) platoon. While the reconnaissance element was composed mostly of 1st Force Reconnaissance Company Marines, they made up only 24 of the 86 members of the detachment. The detachment, though lacking organic aviation, operated under the Marine air–ground task force (MAG-TAF) philosophy of leveraging integrated, complementary capabilities to be more effective than the sum of its parts.
More than half of Det One's Recon Marines were trained United States Marine Corps Scout Sniper (Scout Sniper).
The public source identifies “Det One” as military unit. This brief keeps that definition visible, then builds a research path around military and unit.
Why this record matters
A short description can identify a subject without explaining its stakes. For “Det One”, the useful work is to connect “military unit” to the records capable of establishing context and consequence.
Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 10, 2026. The linked authority identifier is Q6714991. None of the 1 selected statements returned an explicit reference. The first chronological checks are 2003 and 2006.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Det One”, its source revision and the description used here.
- Expand the search: follow Det One primary sources, Det One archive and military research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Det One”?
- Which cited source is closest to the event, object or claim?
- Which institution is responsible for the underlying evidence?
Search terms from this dossier
This entry incorporates text from “Det One” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.