“With profound regret and with continued pride in my gallant troops, I go to meet the Japanese commander. Goodbye Mr. President.” These were the words Major General Jonathan Wainwright cabled to President Franklin D. Roosevelt in May 1942, just before he surrendered his starving command of combined U.S. and Filipino troops to the Japanese forces that had worn them down for months.1 The United States would recover from this defeat in the months and years to come, mobilizing their enormous weight of resources to retake the Pacific with combined amphibious operations. Some of the U.S. naval services’ finest hours marked the effort.
The defeat in 1942 was an example of how expeditionary advanced basing can go wrong. The Philippines provided a signature example of forward naval basing in the Pacific Ocean. But U.S. forces served little strategic importance there and faced a swift defeat. The forward-deployed sea base was meant to project naval power across the ocean, but it was left too exposed, without any support to hold out against a determined assault from a foreign power. Lack of local naval superiority led to its collapse.
This observation from history presents today’s Sea Services strategists with a core question: In an armed conflict with a peer adversary in the South China Sea, would expeditionary advanced base operations (EABO) leave forward-deployed troops too exposed?
Scale and Complexity: Defining EABO
Expeditionary advanced base operations is the current operating concept through which the Marine Corps will help the Navy establish naval supremacy in a contested maritime region. EABO connects to the Navy’s operating concept of distributed maritime operations.
China’s capabilities are considerable and growing, and its long-range missile and rocket systems make operating in the South China Sea difficult for the U.S. Navy. EABO as laid out in the Marine Corps’ Tentative Manual for Expeditionary Operations places U.S. denial assets in China’s own backyard to blunt the capabilities of the People’s Liberation Army Navy (PLAN) in the event of conflict. Operations would likely take place in Taiwan, Okinawa, the Philippines, and other land masses that hem the coast of East Asia. The EABO concept is to place bodies of troops on key islands in and around a contested area. These forces will be armed with enough rockets, missiles, and electronic warfare assets to deny enemy access to the zones in which they operate.2 The terms surrounding this concept are “mobile, persistent, low signature, low maintenance, austere, agile, and temporary.”3 The Chief of Naval Operations’ 2022 Navigation Plan similarly called for distance, deception, and distribution as three of the six force design imperatives for the Navy. Distribution is foundational to EABO: "Distributing forces geographically and in all domains enables them to threaten an adversary from multiple attack axes. Smaller, lethal, and less costly platforms—including manned, unmanned, and optionally-manned—further complicate threat targeting, generate confusion, and impose dilemmas for our adversaries."4
Two factors define an individual EAB, namely scale and complexity.
The scale of EABs can range from large, Marine expeditionary force-supporting bases all the way down to hard-to-detect platoon-sized camps. Here we will discuss EABs that are roughly the size expected of an O-6 level of command, referred to as task units.5 An EAB at this scale is small enough to be expeditionary while carrying the firepower needed to make a strategic impact.
The complexity of an EAB relates to its expected role. An EAB that provided ballistic-missile defense capabilities would have an associated physical and electronic signature. Israel produces the Iron Dome with technology capable of protecting units from missile attacks. It is vehicular-mounted or stationary, expensive and high-maintenance, and it has a very limited usage window—20 shots per medium-range intercept capability (MRIC) unit in a single engagement. While this technology is constantly improving and there are similar reliable assets, none of these weapons are “low profile” or “low maintenance,” and they will certainly require resupply.
The other end of the complexity spectrum delivers the proverbial off-the-grid rifle platoon of commandos. While certainly persistent, low-signature, mobile, and cost-effective, they are difficult to integrate into an effective stand-in force that contributes to the strategic control of a contested maritime area. The capabilities (and relative usefulness) of an EAB are directly related to its visibility, and this paper will refer to EABs that are complex enough to be clearly visible to the enemy.
Preventing Catastrophe
The surrender of the Philippines in 1942 suggests how an EAB could meet with disaster. The defenders of the Bataan Peninsula and Corregidor Island were all that remained of U.S. presence in the Philippines—a presence established more than 40 years prior, and which had served as the main U.S. headquarters in the Pacific. The 1898 Spanish-American War led to the U.S. occupation of the Philippines.6 The following years would see the Philippines secured as a U.S. colony with a strong U.S. military influence, but even then, President Theodore Roosevelt recognized the archipelago as the United States’ “heel of Achilles.”7
From 8 December 1941 to 6 May 1942, U.S. and Philippine forces numbering more than 130,000 fought a withdrawal from Manila to Bataan with their air assets immediately neutralized by Japanese air strikes and the Japanese landing in force. Under orders from the President, General Douglas MacArthur left a deteriorating situation on 11 March. Japanese air attacks and artillery bombardment, coupled with starvation, forced Major General Wainwright’s surrender in May. Wainwright ordered all local commanders to surrender their commands as well, and the U.S. and Philippine forces were rounded up as prisoners of war.8
The archipelago had been a strategic asset for resupply and power projection. Now it was exploited by the Japanese. Important U.S. forces were cut off and served out the rest of the war in captivity. Although it is a different time technologically and politically, there are three challenges the defenders of the Philippines faced in the 1940s that the United States needs to consider as it begins to emplace stand-in forces in the western Pacific.
The first consideration is time. The PLAN has shown commendable patience in its planning. Marinus observes: “As what happened in Europe during the Cold War, implementing the strategy may involve committing combat forces to the region for years or decades, as China seems inclined to play a long game, patiently waiting until it has shaped the conditions that guarantee victory.”
EABO requires extended maintenance and continual update of forward-deployed bases. Currently the 31st Marine Expeditionary Unit (MEU) cruises through the Pacific Ocean periodically, an extremely efficient way to project power in the world’s largest ocean. Controlling that same amount of geographic space using land bases requires a much greater economic commitment. Emplaced bases would likely not get better with time and would run the risk of using decrepit technology and becoming complacent.
Second, the United States needs to consider insurgency while planning. Committing U.S. troops to a territory will almost certainly invite local resentment. John Vrolyk discusses the likelihood of China using proxy wars to weaken the United States without direct confrontation. He states, “Great-power competition . . . is likely to involve a new era of messy global entanglements, ranging from economic rivalry to intelligence operations to full-on proxy warfare and insurgency campaigns focused on the world’s most critical lines of communication . . . Great-power war is the enemy’s most dangerous course of action, but low-intensity conflict . . . is the enemy’s most likely course of action.” China could use this approach to target the EAB network.
Given the recent history of U.S. conflicts overseas, the forward deployment of troops, even in territory inhabited by historical allies, could create problems. China will exploit any weakness it finds, sparking small conflicts that will weaken bases over time.
Finally, distributed stand-in forces in EABs will face resource deficiency if hostilities erupt. The defenders of the Philippines in 1942 were supplied for a comfortable six-month sustainment period. Even without resupply, they were expected to hold on until the U.S. fleet could regroup and relieve their position, whether by evacuation or reinforcement. What the defenders did not account for was the local populace who sought refuge alongside U.S. forces. In the event of a determined attack on one of the proposed EABs, especially on islands like Taiwan or Okinawa, U.S. forces would face a similar dilemma. Bases would be considered havens from hostile attack. Denying support to the people who live nearby would raise political and ethical dilemmas, while providing them protection and supplies would strain logistical capabilities.
The disaster long ago in the Philippines reveals some potential weaknesses in EABO. A heavily equipped and defended position emplaced deep within the enemy’s weapon engagement zone before any conflict begins can become a liability if it is isolated. However, as mentioned earlier, the following years of World War II brought about some of the finest hours of the Sea Services. The Marine Corps and Navy established sea and air dominance and rode their novel island-hopping strategy to control of the Pacific. They were able to maintain supply lines, using deep penetrating strikes and advanced bases in concert with naval and air superiority. In that campaign, a few elements stand out as timeless keys to success in distributed operations and the use of EABs.
Small Units, Big Strategic Implications
First, the connection between EABs and the broader force needs to be tight. Command and control, mutual support, and supply all tend to break down when forces are isolated. An EAB cut off as such will surrender quickly. This is the risk that the push to disaggregate and distribute brings, and it is a risk worth taking only with a robust C2 network and a plan to support EABs. The naval concept of seabasing is one idea that could keep large EABs supplied during a conflict, but it will require a high amount of area access. If an EAB needs urgent resupply during a siege, the area around that base is likely already a kill zone for the PLAN to use against U.S. naval assets. Air resupply and subsurface vessels may be the best means of sustaining supplies to these contested areas.
Second, smaller expeditionary bases should be considered more thoroughly. The concept of distributed forces and expeditionary bases must stay in true keeping with the word “expeditionary.” The small percentage of U.S. forces that escaped after Wainwright’s surrender fought a guerrilla campaign for the remainder of the war. Groups that can covertly insert into the enemy weapon engagement zone, live off the land and local support, and operate as small, low-maintenance units should be central to the plan. Prioritize platoon-sized elements that can make a disproportionate impact on enemy infrastructure. As discussed earlier, the difficulty with a small unit is making it useful on a strategic level, so a major portion of modern EAB planning needs to focus on the development of low-signature, long-range precision weapons that are mobile and easily concealable. An example of this could be several Polaris all-terrain vehicles packed with a long-range variety of Switchblade missiles. Such an asset is truly mobile and could operate without a huge cyber signature, staying concealed while projecting destruction in a high power-to-weight ratio. A small roaming unit of Marines would also face fewer problems with indigenous people and would not carry the same burden of protection that would constrain a larger force.
The Abiding Importance of Amphibious Assault
Third, keep amphibious assault on the table. Amphibious forced entry into enemy territory is hard, but it allows a concerted assault with established and protected external supply lines. The United States should not abandon the strategy of forced entry and opposed landings under the assumption that forward bases will already exist. The Marine Corps must be freed to do what the Marine Corps excels at: amphibious landings and expeditionary warfare. The advent of new technology, namely long-range cruise missiles, has led to claims that amphibious landing is obsolete. Brett Friedman confronts this claim by reviewing the use of amphibious landings throughout recent history and over several ages of technology. Coastal artillery and machine guns were both technological developments expected to render the amphibious landing obsolete, yet innovations in amphibious doctrine overcame these new challenges with great success—albeit high casualties—in the contested landings of World War II. Friedman says that: “Today’s threat is the precision-guided missile. Whether directed at amphibious ships themselves or the ship-to-shore connector—such as the amphibious assault vehicle—these missiles present a significant hurdle to the landing force. . . . But the tactical dynamics have changed drastically since 1944, making precision-guided missiles less of a threat than breathless declarations of game-changing technology purport.”
Friedman goes on to list the helicopter, subsurface assault, and airborne assault as three tools that keep amphibious landings viable. This emphasis on operating in a contested littoral environment should be a priority for Marines and Navy strike teams.
Mutual connection, small lethal forces, and amphibious landing capabilities were keys to failure and success in the Philippines and the subsequent campaign throughout the western Pacific. A robust EABO strategy should take these elements into account as foundations of training and preparation for distributed operations in the Pacific.
History cannot provide a checklist to success. But studying history gives insight on how even the best plans can fall into catastrophe when they meet the unexpected. Although times have changed, and technology has altered the battlespace, the difficulties MacArthur and Wainwright faced in the Philippines can inform strategy today. The current concept of MEU-sized EABs faces the challenges of complacency, becoming a target for insurgent warfare, and having to protect a local civilian populace. A strategy of robust support-and-control networks, truly expeditionary small-unit operations, and Marine amphibious assault should be the foundational focus of training and education in today’s U.S. maritime forces.
1. Allan R. Millett and Peter Maslowski, For the Common Defense (Riverside, CA: Free Press, 2012), 376.
2. HQMC, Tentative Manual for EABO v2, 1-2
3. HQMC, Tentative Manual for EABO v2, 1-2
4. CNO Navigation Plan 2022, 10
5. HQMC, Tentative Manual for EABO v2, 2-5
6. Jack Shulimson et al, Marines in the Spanish-American War, 1895–1899: Anthology and Annotated Bibliography (Washington, D.C.: History and Museum Division, Headquarters, U.S. Marine Corps, 1998), 27.
7. Allan R. Millett and Peter Maslowski, For the Common Defense (Riverside: Free Press, 2012), 281.
8. R. Ernest Dupuy and Trevor N. Dupuy, “World War II in Asia and the Pacific,” The Encyclopedia of Military History from 3500 B.C. to the Present, 2nd ed. (New York: Harper & Row, 1986), 1127–40.
