Just to clarify:
Ground Combat Elements
The basic organization of Marine Corps infantry units follows the "rule of threes", which places three subordinates under a commander, not counting
support elements. The organization and weapons are from the Marine Corps Table of Organization and Equipment standard. Note that these are
principles, but according to manpower and mission needs units can deviate from the TOE (e.g. with 4 subordinate units instead of 3, or a commander who
is a rank above or below the rank specified). Supporting units will have their own organization and equipment, but generally also follow the "rule of
* A fire team is the basic element of the GCE. It consists of four Marines: the team leader/rifleman (M4/M16), one rifleman (M4/M16), one
grenadier (M4/M16 with M203) and one light machine gunner (M249). The team leader is typically a Lance Corporal or Corporal.
* A squad is made up of three fire teams, in addition to a Corporal or Sergeant as squad leader.
* A rifle platoon consists of three squads, and a headquarters element made up of a Platoon Commander, a Platoon Sergeant and a Navy Corpsman. The
Platoon Sergeant advises the commander, usually a 2nd or 1st Lieutenant, in making decisions. A weapons platoon will substitute for the squads a 60 mm
mortar section, an assault section, and a medium machine gun (M240G) section. It is led by a 2nd or 1st Lieutenant.
* A rifle company consists of three rifle platoons, a weapons platoon, and support staff. A weapons company will substitute for the rifle platoons
an 81 mm mortar platoon, an anti-armor platoon, and a heavy machine gun platoon.
There is also a Headquarters and Service Company, consisting of a headquarters platoon, a communications platoon, a service platoon, and the
Battalion Aid Station. It is led by a Captain.
* A battalion consists of three rifle companies, one weapons company, and one Headquarters and Service Company, commanded by a Lieutenant
* A regiment consists of three battalions, led by a Colonel
* A division, commanded by a Major General, comprises three infantry regiments and an artillery regiment, and additional specialized units, such
A brigade, commanded by a brigadier general, is less common in the Marine Corps, but is typically made up of one or more regiments plus support
Battalions and larger units have a Sergeant Major, and an Executive Officer as second in command, plus officers and others for: Administration (S-1),
Intelligence (S-2), Operations (S-3), Logistics (S-4), Civil Affairs (wartime only) (S-5), and Communications (S-6). Units of battalion size or larger
may be reinforced by the addition of supporting tank or artillery units, as in the Battalion Landing Teams comprising the GCEs of Marine Expeditionary