Download PDF
Adam Clemens is a Principal Research Scientist at CNA.
The U.S. Marine Corps is in the process of a bold modernization initiative known as Force Design, and Congress has called for an independent review, assessment, and analysis of this initiative.1 Force Design began during the tenure of the previous commandant, General David H. Berger, and the new commandant, General Eric M. Smith, sworn in last year, endorses it in his official guidance, FR AGO (Fragmentary Order) 01-2024, Maintain Momentum.2 The continuation of Force Design under a new commandant and the congres- sional attention it is receiving provide opportune circumstances to consider the Marine Corps’ roles and missions.
The Marine Corps’ statutory mission—amphibious assault to seize ad- vanced naval bases—is not as relevant as it once was, but it cannot be completely dismissed. The Marine Corps needs a mission or set of missions to ensure its relevance in a 21st-century world in which denied environments will become increasingly common. More important, the Marine Corps cannot simply choose the missions it would like to do and hope that the other Services and Congress accept those choices and that our partners and competitors respond to them in a way that improves the competitive position of the United States. The Marine Corps must instead optimize itself to suit the Nation’s needs given the choices made by other actors.
A new mission set may or may not be a good fit for a force structure built around light infantry and short-range aviation. In this article, my purpose is neither to find missions that best justify the current composition of the force nor to conduct a troop-to-task analysis and prescribe a new force structure tailored to new missions. Rather, my goal is to argue for a new mission set suitable to enduring institutional strengths of the Marine Corps, leaving to future work the detailed analysis of what that mission set will require. In the process, I do note where elements of existing Marine Corps structure and capabilities seem a likely fit, and where it would clearly need some new capabilities and/or organizations.
Current Guidance
The current commandant’s guidance makes four useful assumptions:
- The long-standing trend of increasing dispersion on the battlefield will continue and likely accelerate; front- ages will increase, battlefield depth will increase, and sanctuary will be difficult to achieve.
- Winning the all-domain reconnaissance and counter-reconnaissance fight provides significant warfighting advantage. Losing this fight will be increasingly difficult to overcome.
- The ability to task-organize for specific missions will continue to be a source of competitive advantage.
- The future operating environment requires threat-informed modernization of capabilities.3
Taken together, these assumptions suggest that the Marine Corps will organize into mission-specific command and control structures that involve distributed operations and that at least in some cases contribute to reconnaissance and counter-reconnaissance. This is a starting point to design the force, but the guidance leaves much for others to flesh out. For example, the guidance does not name an adversary, despite the clear direction in the 2022 National Defense Strategy that the Department of Defense is to focus on China.4 It mentions posturing Marine forces for deliberate campaign activities to “deter malign actors, respond to crises, and provide our nation’s leaders with strategic decision space.”5 But which actors are these Marines deterring from what? What are these Marines influencing? Are they shaping conditions toward some desired endstate? It will be difficult to optimally design Marine forces with- out a clearer goal.
Similarly, the commandant’s guidance asserts that “Stand-In Forces” have potential to contribute to the joint force and that Marines are the eyes and ears of this force. But it does not elaborate on how much of the Marine Corps will contribute to this mission, or whether it will need another explanation for what it is doing in theater while it is collecting information for the joint force, or what other potential these forward-postured forces must contribute to the broader joint mission.
Finally, the guidance advocates for L-class amphibious warfare ships and places a high priority on crisis response. While it is true that a Marine Expeditionary Unit (MEU) embarked on amphibious ships is capable of responding to a variety of low-level crises and that combatant commanders value the MEU, crisis response is no longer the best argument to justify the MEU, let alone the entire Marine Corps.6 CNA’s analysis of the history of Marine Corps operations reveals that the MEU has seldom been employed as a whole and is therefore an expensive approach to crisis response. However, while providing a forward presence for Great Power competition, it can be used for crisis response as a side benefit.
These issues point to the need for other missions by which the Marine Corps can contribute to U.S. strategy and put pressure on China. It should structure itself for low-intensity or expeditionary roles that other Services are not pursuing. Rather than focusing on crisis response as key to its value proposition, it should embrace the challenge now of expanding its presence for competition. Maximizing its value in this competition will require a mix of old and new capabilities.
Three Ways to Support Great Power Competition
Fortunately, the Marine Corps is uniquely suited for three mission areas relevant to Great Power competition. It can:
- contribute to the developing power balance in the Western Pacific with a small footprint, supporting the capabilities of local partners
- offer an expeditionary force to counter Chinese or Russian expeditionary forces in other theaters, such as the Indian Ocean and Africa
- field a force organized and trained to seize ships—simultaneously imposing strategic costs on China and providing the United States with more platforms to complicate targeting efforts—in the event of war.
More important, a force with the naval agility to seize ships, the mass and capability to counter Chinese or Russian forces, and a foothold in the Western Pacific would certainly be in no worse a position than the current force to seize naval terrain, including naval bases.
First, each of these mission areas is based on a Chinese strategic vulnerability. China is not the only technologically advanced country in its region, nor the only one with rapid economic growth, nor the only one working aggressively to expand and modernize its military capabilities. To make matters worse, it has no friends and several unresolved territorial disputes. In fact, of the 3 million square kilometers of ocean that China claims as territorial waters or exclusive economic zone, more than half is involved in territorial disputes with China’s neighbors.7 These neighbors are invested in defending their claims. For example, in 2020, navy and air force spending in the eight countries with which China has maritime territorial disputes added up to 53 percent of China’s own.8 The United States can therefore play a supporting role in maintaining the local balance of power, and the Marine Corps is ideally suited because of its experience in supporting the security forces of less advanced partners and because the theater’s primary interest is maritime security.
Second, China’s Belt and Road Initiative to invest in infrastructure linking Eurasia and Africa expands its security concerns and its need for expeditionary forces. China now has interests not only throughout the Indian Ocean but also from Kenya to the Netherlands. The Department of Defense confirms that China is expanding its People’s Liberation Army Navy Marine Corps, as China announced, to increase its expeditionary capabilities.9 We know that China has military facilities in the Horn of Africa (near the U.S. base Camp Lemonnier) and in Pakistan.10 As China prepares to flex its muscles in response to risks abroad, it should realize the United States also can operate an expeditionary force wherever China does. Russia also has expeditionary capabilities and a growing interest in Africa, and the United States needs the capability to counter.11 A force designed to be effective against Chinese forces would also be more survivable in other denied environments against other revisionist states or nonstate actors.
Third, “China’s economy is highly dependent on overseas trade, and its merchant marine is the world’s largest. Consequently, its need for maritime security and open sea routes is acute.”12 The threat of losing its commercial ships during a war would increase Chinese hesitance to risk a war, and if such piracy began, history suggests it would significantly increase the domestic pressure to end the war. Although sinking Chinese merchant vessels is one option, the United States needs a way to acquire ships for a war because it does not build them. The United Nations Conference on Trade and Development reports that 94 percent of shipbuilding in 2021 occurred in China, South Korea, and Japan. In 2021, China produced 884 times as many ships as the United States (44.2 percent vs. 0.05 per- cent of the world total).13
Western Pacific Presence
The geopolitical importance of the Western Pacific theater is beyond dispute, and to the extent that the Marine Corps can contribute to competition there, it should. If Marines can help partner countries improve their capacity for maritime intelligence, surveillance, and reconnaissance and sea denial, it can contribute to a multilateral power balance and reduce the risk of a direct conflict with China. It may want to secure agreements to pre-position equipment and supplies in the Philippines, Indonesia, Singapore, Malaysia, Vietnam, and/or Thailand, and perhaps in the Indian Ocean countries of India and Bangladesh. Airborne intelligence, surveillance, and reconnaissance systems and patrol craft are an obvious place to start; several countries in the region are interested in these capabilities, and they contribute to all four levers of national power.
In addition, to the extent that political will allows, the Marine Corps can work to further U.S. influence and mitigate Chinese influence by employing a variety of noncombat arms capabilities. Civil affairs Marines (1732 and 0531) can build relationships with civil leaders and conduct reconnaissance of human terrain. Communication strategy and opera- tions Marines (45XX) can amplify the U.S. narrative. Judge advocates (4402) can defend U.S. interests and help host countries to counter Chinese claims and bring suits against Chinese malign activi- ties. Communications Marines (06XX) can support local cyber security and the installation of new IT infrastructure in re- mote areas. Navy health professionals and chaplains assigned to Marine command structures, supported by logistics (04XX), utilities (11XX), engineering (13XX), and supply (30XX) Marines, can coordinate humanitarian assistance. All these occupations, traditionally thought of as “enabling capabilities,” may collectively form the main effort in steady-state competition.
One benefit of this increased presence and influence is that it may raise the probability of access to and/or the capability of logistics nodes ashore during crisis or conflict, expanding the employment options of the joint force. In fact, the Tentative Manual for Expeditionary Advanced Base Operations mentions forward sustainment of the joint force as a mission of such operations.14
If the small footprints of Marines doing this work ashore did operate from a larger sea-based force, it would increase the Marine Corps’ ability to transition from the contact layer (which is “designed to help us compete more effectively below the level of armed conflict”) to the blunt layer (which is designed to “delay, degrade, or deny adversary aggression”) in a contingency.15 However, it is unclear to what extent the Navy will support that vision beyond the existing Amphibious Ready Group (ARG)/MEU.
Counter-Expeditionary Force
The current mix of ground- and air-based Marine Corps capabilities may be most useful not against a less-capable adversary such as Iran, but against forces of a peer competitor operating far from its home bases and associated defensive umbrella. A Proceedings article argues that “the expeditionary threat of Chinese and Russian expansionism calls for a near-peer ‘9-1-1’ response capability, for which the Marines are uniquely suited.”16
Conveniently, and unlike the other two mission areas described here, this mission fits with existing Marine structures and employment models. Marines could build a Marine Expeditionary Brigade (MEB)-sized force in response to indications and warnings that an adversary was doing the same. It would require joint enablers, not only to create strategic lift but also likely to neutralize advanced air defense systems that China or Russia deployed forward and that were beyond the organic capability of the Marine forces to suppress—unless the force could accomplish its mission without tactical aviation. Increased air-defense capability within the Marine Corps would enhance the ability of these expeditionary forces to operate independently (and enhance what the Marines can offer partner nations in the first mission area described above). Ground forces that are better equipped for air defense, less reliant on organic air support, and trained for signature management and electronic warfare to survive a capable adversary would also remain effective against less capable adversaries as their sensing and denial capabilities grow.
Pirate Force
In a vignette considering how to impose strategic costs in a conflict with China, the Center for Strategic and International Studies assumes that the U.S. military would not initially have its own capability to seize Chinese merchant vessels. It describes chartering the U.S. private sector to do so at the expense of some international discomfort and later converting the privateer ships to warships with U.S. markings and under the command of U.S. officers.17 It would be even more effective if this force existed in advance as a deterrent and were already a U.S. Government operation.
A simple approach, effective against poorly prepared merchants, would use small boats with hook ladders and/or a helicopter to deposit troops on the ship, who then employ small arms and non- lethal weapons to squash any resistance from the crew. In fact, ARG/MEUs already have a visit, board, search, and seize mission. A stronger assault to capture or sink better-defended ships could involve a combined arms Marine Air-Sea Task Force (MASTF), with some combination of missiles, loitering munitions, machine guns, and specially trained infantry, all operating from boats.18 The political opposition to this more violent approach may be stronger, and once the United States has crossed this line (and damaged the ships in the fight) it may choose to sink them instead, but it should retain the option to employ them as logistics and potential fires platforms in order to complicate China’s targeting problem. In either case, there would be a need for a mother ship from which to launch the boats and possible helicopter, but this could be cost-effective and perhaps converted from an existing commercial vessel.
What About the Statutory Mission?
If a Marine Corps built for these missions were then ordered to seize a naval base, it would have better means to do so than massing amphibious assault ships just off the shore. It would already be trained to operate with a mix of commercial vessels—which it is familiar with both operating from and seizing—and smaller boats. It would also have a variety of sensing and fires assets designed to be relevant against 21st-century technology. Imagine several MASTFs appearing in one place, borne there by commercial vessels and aggregating into an invasion force, supported by joint fires from over the horizon and backed by at least an MEB-sized follow-on force waiting to flow in as conditions allow. This would hardly be an abandonment of amphibious assault.
The U.S. Marine Corps needs to adapt to 21st-century roles that strengthen the competitive position of the Nation. Three roles that do so are maintaining a steady-state presence in the Western Pacific to support and maintain influence in partner countries surrounding China; maintaining a credible force to counter Chinese or Russian adventurism abroad; and preparing forces to capture ships to impose strategic costs on China’s shipping-dependent economy. The optimal force structure for these missions will require further analysis, but boats; maritime intelligence, surveillance, and reconnaissance systems; and air defense assets are likely requirements. JFQ