The Marine Corps is inverting its traditional understanding of the relationship between land and sea. According to Commandant of the Marine Corps General Eric M. Smith in FRAGO 01-2024, “With Force Design in place, we will continue our proud history as our nation’s expeditionary shock troops that can deliver combat power from sea to land—now with the additional capability to project power from land to sea.” (Emphasis in the original.)
The Marine Corps has been a maritime service since its founding, but never before has it viewed the sea as one of its primary warfighting domains. As one naval strategist notes, “The use of Marine Corps units to contribute to Navy sea-denial operations against an opposing navy by launching antiship cruise missiles represents an entirely new mission for the Marine Corps that does not take it back to its roots.” The service’s new focus on sensing, maneuver, and fires oriented on the maritime domain is a break from the past. This presents the service with profound challenges but also rich opportunities to help the joint force win the nation’s battles at sea.
Prior to Force Design, the Marine Corps embraced two primary warfighting domains—ground and air—and the service-level function of global crisis response. Force Design added maritime as a third domain and multidomain reconnaissance/counter-reconnaissance as a second service-level function—but without increased resources. The service has navigated changes at this scale before.
In the early 20th century, the Marine Corps added air as a new warfighting domain and large-scale amphibious operations as a service-level function. It successfully adapted to these changes and played a critical role in U.S. victory in the Pacific during World War II. To repeat this feat and enable success in another potential war in the Pacific, the service should apply lessons from that earlier era: Deliver early operational results in the maritime domain, establish institutional advocacy and expand integration with the Navy, and consider a new maritime reconnaissance/counter-reconnaissance operational formation.
Challenging Changes
The Marine Corps has used the sea for basing and for transit to enable expeditionary operations ashore since the Continental Marines first embarked on warships. Marines even occasionally attacked enemy vessels during this era, foreshadowing Force Design’s focus on engaging maritime targets.1 But the service is diverging from the past by embracing large-scale land-to-sea warfighting. Marines based primarily ashore will use antiship munitions, crewed and uncrewed surface vessels, and sensors in multiple domains to fight, sense, and generate effects at sea. This is similar to Marine aviation deploying capabilities from land to conduct warfighting in the air. The maritime space is now a warfighting domain rather than a transit area.
The service’s new reconnaissance/counter-reconnaissance function is maritime-centric but broader in scope. It also encompasses air, ground, and multiple secondary domains such as cyber and space. Reconnaissance collects relevant information about an adversary while counter-reconnaissance prevents the adversary from doing the same. This is analogous to the naval functions of scouting and screening. According to General Smith, “We are the eyes and ears for the joint force, ideally positioned within the [weapons engagement zone] to conduct both reconnaissance and counter-reconnaissance, to act as a Joint Fires integrator for the combined force, and to strike the enemy from land and air to sea with organic sensors and precision fires, when necessary.” Overall, the service’s new maritime warfighting domain emphasizes where to focus operations, and its new function describes on which operations to focus.
The service also is enhancing air and ground combined-arms capabilities and its global crisis response function. One of the Commandant’s top priorities is “balancing crisis response and modernization,” which acknowledges the tension between maintaining the service’s legacy role and leaning into its new warfighting domain and function. The Commandant wants to extend combined-arms operations to all domains and use crisis response forces for theater campaigning. This places additional requirements on the service.
How can the Marine Corps successfully break into a new domain, implement a new service-level function, and enhance its traditional function without significant additional resources? The dramatic changes the service implemented in the early 20th century prove it is possible and provide clues about how to do it again.
Early Operational Results
To convince skeptics about the value of its third warfighting domain and obtain the necessary resourcing, the Marine Corps must be able to demonstrate tangible operational successes in that domain. When faced with a similar dilemma in the early 1900s, Marine aviators provided incontrovertible evidence about their operational worth by demonstrating their capabilities in combat and force-on-force exercises. Using lessons from these activities, they reinforced successes and allowed subpar capabilities and tactics to “fail fast.”
In 1914, before Marine aviation formally existed, Marine aviators joined an important force-on-force exercise in Culebra, Puerto Rico, with Marines from the Advance Base Brigade. Aviators flew scouting and reconnaissance missions, demonstrated the vulnerability of battleships to aerial bombing, and took officers from the supported unit on daily flights to experience the operational relevance of the air domain. During World War I, Marines flew combat missions in France and antisubmarine missions from the Azores. In the 1920s, they developed dive bombing tactics in Haiti and flew their first close-air support mission in Nicaragua. Resistance from the Navy and Congress withered as Marine aviation’s operational successes mounted, generating steady increases in personnel and funding.2
When funding decreased after the Great Depression, Marine aviation adapted by cutting noncritical capabilities and tactics to focus on close-air support to Marines on the ground. In 1929–30, it abandoned its airfield for lighter-than-air capabilities and abolished balloon units. In 1936, during a large-scale landing exercise, aviators eliminated a smoke screen tactic after learning it disrupted assault boats by reducing crew visibility. Aviators also learned they needed a specialized attack aircraft to provide effective close-air support, so they redoubled efforts to obtain this capability.3
The Marine Corps today cannot test new capabilities in combat, but it can highlight the effectiveness of analogous Ukrainian capabilities against Russia in the Black Sea. Ukraine has used antiship missiles and unmanned aircraft and surface vessels for reconnaissance and attack missions to sink or severely damage at least 15 Russian warships. Although unmanned surface vessels are vulnerable to helicopters, some are now being armed with antiaircraft missiles. This is strong evidence to support the effectiveness of similar Marine capabilities. Competition does not approximate combat, but fielding new capabilities to the Pacific soon would improve campaigning and demonstrate that the capabilities are well positioned for combat.
The Marine Corps can prove operational relevance in the maritime domain through force-on-force exercises against Navy warships. The service should prioritize exercises that include live red forces that attempt to defeat new Marine capabilities. As it learns, the Marine Corps could cut noncritical capabilities and functions and reinforce those that best support reconnaissance and counter-reconnaissance. Aggregate evidence from Ukraine’s successes, Marine capabilities in the Pacific, and force-on-force exercises could help convince skeptics and secure resources.
Advocacy and Integration
The Marine Corps should institutionalize maritime warfighting, but it needs the Navy’s expertise and bureaucratic capacity to do it. In its early years, Marine aviation established effective service-level advocacy and maintained deep integration with Navy training, basing, supply, and administration. The Marine Corps could use this as a model for institutionalizing maritime warfighting.
Early Marine aviation enmeshed its nascent organization in Navy bureaucracy to ensure Marines were trained, manned, and equipped for aerial warfighting. Some of these organizational relationships continue to this day.
In 1919, because it depended heavily on the Navy for aircraft, supplies, and training facilities, Marine aviation was placed under both the Commandant and the Navy’s Director of Naval Aviation. In 1920, the small Marine Aviation Section came under the Division of Operations and Training at Headquarters Marine Corps, giving aviators formal institutional advocacy. In the 1930s, the section was upgraded to a full division directly under the Commandant, which helped it defend its interests and negotiate command relationships. The division director also served as liaison with the Navy’s Bureau of Aeronautics. In addition, the Marine Corps used the Navy’s pilot training pipeline and bases to host units and facilitate experimentation. Marines returning from aircraft carrier deployments brought back new training standards that the service codified to help professionalize Marine aviation.4
Institutional advocacy and integration with the Navy are just as critical today. The Marine Corps could create a division under the Deputy Commandant for Plans, Policies, and Operations to advocate for maritime warfighting and reconnaissance/counter-reconnaissance equities and interface with relevant entities in the Office of the Chief of Naval Operations. This would enable it to take full advantage of Navy training, basing, matériel, and supplies and would be critical for developing integrated processes for maritime targeting and employing on-the-water Marine capabilities such as crewed and uncrewed surface vessels.
A New Operational Formation
Early Marine aviation units were frequently reorganized. They eventually were consolidated into Aviation Groups and then a Marine Aircraft Wing (MAW) in 1941. The MAW provided a higher-echelon staff to plan and advise on aviation operations for the Fleet Marine Force or Navy Battle Force commander. Early units had a clear operational purpose: provide close-air support to the Advance Base Force. This mission later was broadened to include supporting any Marines on the ground. Today, the service could create a higher-echelon command for maritime warfighting that provides reconnaissance/counter-reconnaissance for the joint force.
A maritime reconnaissance/counter-reconnaissance command could be led by a general officer in each Marine expeditionary force (MEF). It would differ for each MEF but generally could consist of elements pulled from division, including reconnaissance and light armored reconnaissance battalions and antiship artillery units, as well as the MEF Information Group (MIG). This would give each MEF a general-officer command for each of the three primary warfighting domains: the division focusing on ground, sea-to-land amphibious operations, and traditional crisis response; the MAW focusing on aviation; and the new command focusing on maritime and land-to-sea reconnaissance/counter-reconnaissance operations.
Because 3rd Marine Division already has maritime-centric Marine littoral regiments, the only change would be folding a portion or all of III MIG into the division to reinforce the reconnaissance portion of its maritime mission. I and II MEF could carve out maritime-centric units from each division and fuse them with at least a portion of each MIG to create new general-officer commands. This construct may not be the best or even most feasible solution, but the key point is that the service should continually reevaluate whether its organizational constructs best enable maritime reconnaissance and counter-reconnaissance.
Conclusion
The Marine Corps faces the daunting challenge of fighting in a new maritime warfighting domain and adopting a new service-level function while maintaining its traditional domains and crisis-response function—all without additional resources. The service successfully adapted to changes of this scale before, and while history suggests the transition may be painful, it could yield enormous dividends by enabling the Marine Corps to help win the nation’s battles in the air, on land, and now directly at sea.
1. Benjamin Armstrong, Small Boats and Daring Men: Maritime Raiding, Irregular Warfare, and the Early American Navy (Norman: University of Oklahoma Press, 2019).
2. Edward C. Johnson, Marine Corps Aviation: The Early Years 1912–1940, ed. Graham A. Cosmas (Washington, DC: History and Museums Division, Headquarters Marine Corps, 1977), 6–7, 27–30.
3. Johnson, Marine Corps Aviation, 61, 79.
4. Johnson, Marine Corps Aviation, 30, 66, 76.
