Over the past 17 years fighting counterinsurgencies, the Marine Corps has often operated within landlocked areas under the umbrella of uncontested air superiority. As the service transitions back to the sea, its ability to carry out its mission will require innovative solutions to the timeless challenge of seizing and defending advanced naval bases within contested air and maritime domains. The Marine Corps must increase its ability to seize, defend, and provide critical power projection from bases inside the enemy’s area of influence—what has become known as expeditionary advanced base operations (EABO).
This concept, however, is not new. Before World War II, the Marine Corps developed coastal defense battalions whose mission was to defend advanced naval bases in support of the ensuing naval campaign in the Pacific. (See “Fight Inside an Adversary’s Weapons Engagement Zone,” pp. 32–35, April 2019.) This model, adapted to 21st-century operating concepts, will be the foundation for how the Marine air-ground task force (MAGTF) seizes, defends, and projects power “to support sea control and sea denial, and allow freedom of maneuver for naval and joint forces.”1 The Marine Corps should create sea-control battalions that have the organization, equipment, and training required to support EABO.
Marine Defense Battalions
The Marine Corps developed its defense battalions in the 1930s to meet requirements similar to its current Title 10 responsibilities. Specifically, Title 10 stipulates that “The Marine Corps shall be organized, trained, and equipped . . . for service with the fleet in the seizure or defense of advanced naval bases and for the conduct of such land operations as may be essential to the prosecution of a naval campaign.”2 Ahead of World War II, the United States identified various Pacific islands as prospective naval bases to be occupied and used as forward aircraft runways, refueling, and rearming positions in the event of war with Japan. The positions became critical to the naval force as the United States maneuvered across the Pacific during the island-hopping campaign, and they required coastal defense units to occupy and defend them against Japanese attack.
Over time, Marine defense battalions altered and shaped their tables of organization and equipment (TO&E) based on the mission and enemy threat. By the time the war in the Pacific reached its height, each Marine defense battalion had almost 900 men spread across a task organization of three seacoast and antiaircraft batteries, ground machine-gun batteries, antiaircraft machine-gun batteries, and a team of specialists in administration and weapon maintenance.3
Although the defense battalion model was successful in the Pacific war, today’s environment will require an updated model with a revised mission and TO&E to meet the joint force’s requirements for sea control, sea denial, and power projection against a modern adversary.4
The Marine Corps Operating Concept (MOC) describes EABO this way:
MAGTFs may be task-organized for missions to seize, establish, and operate multiple EABs. We must improve our ability to: employ EABs for offensive actions in support of sea control; reinforce and defend EABs with manned and unmanned long-range strike, anti-ship, anti-air, and C2-extending systems to transform a site into a sea-denial outpost.5
Although the Marine Corps arguably has the capability to execute this mission, the service generally—and MAGTFs specifically—are not organized or trained to do so. In contrast to the defensive mission of World War II defense battalions, the MOC emphasizes offensive EABO actions:
Critical to the sustainment and success of this distributed fleet will be a proliferation of advanced bases that can survive and thrive within the arc of enemy long-range systems and rely upon largely passive defenses to provide essential services to a more distributed fleet and enable our legacy ships to reload forward. Naval forces will seize, occupy and defend these less predictable and lower signature expeditionary advanced bases to provide joint force maritime component commander (JFMCC) with “sensors, shooters and sustainment” in support of sea control.6
A new task-oriented organization model, the sea-control battalion, is required—a model that would offer scalable and flexible options to meet the needs of the joint force.
Sea-Control Battalion Task Organization
Sea-control battalions should be modular, tailorable, highly mobile force multipliers that offer the ability to pick specific units to deploy in support of the naval campaign. In addition, they should be distributable, with increased lethality but minimal logistics requirements to make them difficult and dangerous to target. Multiple and dispersed locations force the enemy to honor each threat, tying up his critical target-acquisition assets, increasing his kill-chain processes, and ultimately overwhelming his ability to make timely decisions.
Sea-control battalion task organizations could be built on the framework of Marine defense battalions with modern updates. Each would comprise artillery batteries, ground-based air-defense (GBAD) batteries, ground-based radar platoons, Marine unmanned aerial vehicle (UAV) squadrons (VMUs), and infantry companies.
Hosting these capabilities within composite units offers the most flexibility, because they can field capabilities organized by appropriate tasks based on mission, enemy, terrain, time, troops available, and civilian considerations (METT-TC). Each EAB would have an officer in charge exercising overall administrative control of all subordinate units within his area of operations. Individual units would operate with decentralized command and control, supporting the joint force within their areas of influence and acting as an extension of the power projection arm of the naval force within the composite warfare commander construct. For example, an M142 High Mobility Artillery Rocket System (HIMARS) battery might answer a call for fire from the surface warfare commander, who is responsible for “operations conducted to destroy or neutralize enemy naval surface forces and merchant vessels.”7 Many other capabilities could be employed similarly thanks to the modular nature of sea-control battalions.
Equipping the Battalions
Sea-control battalions will require a variety of systems to perform their missions. Artillery fire-support systems would comprise both traditional HIMARS launchers and emerging fires technology such as the HIMARS-Unmanned Ground Vehicle (UGV). The artillery systems should not be limited to Marine Corps systems, but instead might be equipped with rockets and missiles from across the Department of Defense, such as the M31A1 Guided Multiple Launch Rocket System-Unitary (GMLRS-U) and Army Tactical Missile System (ATACMS). At present, GMLRS and ATACMS only allow HIMARS to engage surface-to-surface, land-based targets, but an antiship cruise missile (ASCM) variant is in development.8 Armed with ASCMs, these batteries would extend power projection inside the enemy’s area of operations, which previously had been considered an antiaccess/area-denial environment. Containerized ASCMs might be positioned and concealed ahead of open conflict, to be operated remotely to increase capacity and remove personnel from higher risk areas.
GBAD systems would include the “two complementary Marine Air Defense Integrated System (MADIS) variants [integrated on Joint Light Tactical Vehicles (JLTVs)]. Both MADIS variants will have optics, gun, and [radio-frequency] defeat [counter-UAV] system.”9 MADIS would be able to support sea-control battalions in ways similar to present low-altitude air-defense units, but with upgrades that will make them more mobile and versatile and extend their reach to interdict aviation and missile threats.
Ground-based radar would include the Marine Corps Ground/Air Task-Oriented Radar (G/ATOR) Blocks 1 and 2. Combined with MADIS, G/ATOR would enable sea-control battalions to track, engage, or provide early warning of enemy aviation, rocket, artillery, and missile threats at considerable distance from EAB positions and the joint force.10
Sea-control battalion UAV support would consist of the RQ-21 Blackjack and the RQ-20A Puma. The Blackjack’s electro-optical, infrared, and laser rangefinders and markers would allow sea-control battalions to observe, track, and target enemy maritime and land-based forces out to 50–100 nautical miles and extended operational ranges.11 Most important, the RQ-21’s minimum support requirements make it ideal for expeditionary operations. According to navaltechnology.com, “The lower logistics footprint ensures deployment from small sites and ship decks. The [UAV] supports tactical operations on land and at sea as it doesn’t need a runway for landing.”12
The RQ-20A Puma would provide a local intelligence, surveillance, and reconnaissance (ISR) capability. Sea-control battalions would employ these to cover gaps in their security perimeter for increased battlespace awareness out to 10 nautical miles.13 In addition, integrating low-cost UAV swarming technology (LOCUST) would saturate the battlespace with ISR, electronic warfare, and autonomous strike platforms.14 Combined, these assets would extend the sensors of the joint force without risk to manned aircraft or crew.
Infantry companies would provide force protection for sea-control battalions. They would conduct reconnaissance and select all potential EAB positions prior to occupation by follow-on units. These infantry companies would be responsible for local security, including patrols of surrounding areas to defend against enemy reconnaissance or attacks. In addition to their standard combat load, they would employ Lethal Miniature Aerial Missile Systems (LMAMS) with modular payloads such as Switchblade for beyond-line-of-sight targets.15
Marines assigned to sea-control battalions would train in a variety of ways. Individual Marines would complete their military occupational specialty’s (MOS) training pipeline to ensure they have the technical foundations. Following assignment to a sea-control battalion, Marines would conduct platoon-, company- or battery-, and battalion-level training in concert with MOS cross-training. Cross-training would enable a broader understanding of tasks across the composite unit, increasing cumulative proficiency and lethality. Field exercises would take place in environments that are most similar to the austere expeditionary conditions they would encounter forward deployed, such as San Clemente Island or the U.S. Virgin Islands.
Finally, as the capstone training event, these battalions would participate in the Joint Exercise Program (JEP) Tier 2 to assess their ability to contribute to the combatant commander’s requirements.16 Sea-control battalions would execute Tier 2 joint task force (JTF) training “designed to assist the [JTF] Commander in preparing for the conduct of complex military operations at the operational level of conflict.”17 Conducted in areas of potential future conflict, JTF training would be an all-encompassing dress rehearsal across the force that demonstrates U.S. capability and willingness to allies and potential adversaries.
Winter Is Coming
As the door closes on almost two decades of counterinsurgency operations, the Marine Corps will once again return to its naval roots, integrating with the Navy, to play a significant role in sea control and power projection to counter peer adversaries in the maritime domain. The World War II Marine defense battalions provide a strong model on which to base EABO organization, but new operating concepts will be required. The time is now to build and field composite units that can offer flexibility to commanders as they test these new concepts. Just as the Fleet Problem exercises of the 1930s helped create the doctrine that would win World War II, EABO activities and exercises today should focus on preparing for a high-end fight against an enemy who has spent decades studying the limitations and weaknesses of the U.S. military.
1. Headquarters, U.S. Marine Corps, “Marine Corps Functional Concept for Marine Air Ground Task Force Fires” (September 2017), 1.
2. Title 10—Armed Forces, U.S.C § 8063 (2018).
3. Charles D. Melson, Condition Red: Marine Defense Battalions in World War II, (Washington, DC: History and Museums Division, Headquarters, U.S. Marine Corps, 1996), 3.
4. “Sea-control operations” are designed to secure use of the maritime domain by one’s own forces and to prevent its use by the enemy. Sea control is the essence of seapower. See U.S. Navy, “Command and Control for Joint Maritime Operations,” Joint Publication [JP] 3-32 (7 August 2013), I-3. “Sea denial” is the partial or complete denial of the adversary’s use of the sea, with a force that may be insufficient to ensure one’s own forces’ use. See Headquarters, U.S. Marine Corps, “Littoral Operations in a Contested Environment” (2017), 26; “Power projection,” in and from the maritime environment, includes a broad spectrum of offensive military operations to destroy enemy forces or logistic support or to prevent enemy forces from approaching friendly forces within enemy weapons’ range. See JP 3-32, GL-6.
5. Headquarters U.S. Marine Corps, Marine Corps Operating Concept (MOC), How an Expeditionary Force Operates in the 21st Century (Washington, DC: Headquarters U.S. Marine Corps, September 2016), 13.
6. Col. Art Corbett, USMC (Ret.), “Expeditionary Advanced Base Operations: Considerations for Force Development” (working paper), Marine Corps War-fighting Lab, Concepts and Plans Division, Marine and Naval Concepts, 27 July 2017, 3.
7. Navy, JP 3-32, xii.
8. Bryan Clark and Jesse Sloman, “Advancing Beyond the Beach: Amphibious Operations in an Era of Precision Weapons,” Center for Strategic and Budgetary Assessments, 15 November 2016, 25.
9. U.S. Marine Corps, “2018 Marine Aviation Plan,” 118.
10. Marine Corps, “Marine Aviation Plan,” 114.
11. Marine Corps, “Marine Aviation Plan,” 88.
12. Naval Technology, “RQ-21A Blackjack Small Tactical Unmanned Air System (STUAS).”
13. Marine Corps, “Marine Aviation Plan,” 89.
14. Raytheon, “Coyote UAS.”
15. AeroVironment, “Switchblade.”
16. Chairman of the Joint Chiefs of Staff Instruction, “Joint Training Policy for the Armed Forces of the United States,” CJCSI 3500.01H, 25 April 2014, B-5–B-6.
17. Chairman’s Instruction, “Joint Training Policy,” B-6.