Access Denied? The Future of U.S. Basing in a Contested World
In November 2020, the U.S. secretary of the Navy publicly expressed interest in establishing a 1st Fleet in the Indian Ocean. While the Navy currently patrols in the Pacific Ocean with the 7th Fleet, based in Yokosuka, Japan, it hoped that another fleet farther southwest would better enable it to cover the entire Indo-Pacific region. The country mentioned as a potential host — Singapore — appeared to balk at the idea.
This experience is symptomatic of a broader challenge facing every branch of the U.S. military: a contested basing environment. Efforts to secure military access overseas will increasingly confront physical, commercial, and political challenges. The physical challenges to U.S. bases stem from the operational approaches of America’s adversaries, particularly so-called “anti-access/area denial” (A2/AD) capabilities, while commercial and political challenges concern potential partners who might be reluctant to provide access due to economic pressures from competitors. These dynamics may be most acute in the Indo-Pacific, where global U.S. power projection needs are shifting in light of China’s growing economic and military clout.
To square its strategic needs with operational and political realities, the United States should adopt a new, hybrid approach to basing that combines elements of the Cold War model — large, concentrated bases in key allies — and the Global War on Terror model — small dispersed bases scattered across informal partners. The Biden administration should tailor its security cooperation and economic strategy to attract partners, balance its need for more options against resource constraints, and revisit global posture plans to achieve this approach.
Challenges to Basing
A worldwide network of bases underpins the United States’ global command of the commons. The Defense Department’s base structure reports acknowledge more than 600 facilities across eight U.S. territories and 45 countries. Many smaller locations fall below the size and value thresholds for reporting, so the actual number is almost certainly much higher. In exchange for access, hosts receive an array of benefits, including alliance treaty protections, aid, arms, base rents, or contracts for local firms. Access is broader than basing and can range from overflight rights to permanent garrisons. Our research focuses on bases, which endow U.S. forces with staying power by serving as sources of housing, resupply, and storage, and are visible demonstrations of U.S. presence. But the ways in which hosts sanction base use also matter since hosts can regulate the sorts of weapons systems that can be stationed and the contingencies in which facilities can be used.
The U.S. network of bases — as well as any future efforts to relocate or expand it — is subject to three forms of contestation that make it politically and operationally vulnerable. The first is physical, stemming from adversaries’ ability to rapidly destroy U.S. infrastructure and equipment from afar using A2/AD capabilities such as ballistic and cruise missiles, submarines, and air defense systems. Pessimistic assessments suggest that China, for example, could decimate U.S. air and sea bases in the Western Pacific within days. Russian and Iranian missiles pose similar challenges for U.S. bases in Europe and the Middle East as well. The U.S. military is well aware of the risk. Indeed, the 2018 National Defense Strategy explicitly calls for new approaches to basing designed to minimize the physical vulnerabilities of U.S. infrastructure and equipment.
Second, U.S. bases are subject to commercial contestation from American competitors, especially China. Countering China’s economic influence is core to the focus on strategic competition envisioned in both the 2018 National Defense Strategy and the 2017 National Security Strategy. Many current and prospective base hosts such as the Philippines, Cambodia, and Singapore have deep economic ties with China, the largest trading partner of almost every country in East Asia, that have only grown as a result of China’s Belt and Road Initiative. This gives the government in Beijing indirect leverage to prevent or curb U.S. access by threatening to cancel infrastructure projects or cut commercial ties, as happened in the Northern Marianas Islands.
China might soon find itself with direct leverage as well. Chinese firms in recent years have gained major stakes in, for example, a number of ports that might be useful for the U.S. Navy, such as Djibouti’s Doraleh multi-purpose port. China could undermine U.S. interests in the Middle East and the Horn of Africa if it called in Djibouti’s substantial debt and took control of the port — as it did when it acquired Sri Lanka’s port at Hambantota in 2017 — or pressure the government to limit U.S. access. Even if China avoids overtly denying U.S. access in strategic locations like Djibouti, the operational implications of limiting, delaying, or surveilling U.S. military movements could be significant.
The third form of contestation is political, stemming from potential partners’ reluctance to host a U.S. presence. There is a long history of some local populations resenting the consequences of hosting U.S. military forces, including environmental and noise pollution and crimes committed by U.S. servicemembers. At the national level, political challenges are often exacerbated by commercial contestation. In East Asia, many prospective hosts worry that appearing too close to the United States would invite Chinese retaliation. Chinese-imposed sanctions on South Korea for accepting the U.S. Terminal High Altitude Area Defense system in 2016 contributed to widespread domestic protests. Though the controversy was over a new weapons system, not a new base, it illustrates how economic coercion could induce changes to U.S. military posture. Other states might reasonably imagine that China would sanction them too.
These forms of contestation can interact to create political, strategic, and operational dilemmas for the United States. For example, the United States uses forward presence to reassure allies that it has skin in the game and is willing to accept costs on their behalf. Such assurances signal that the United States will defend allies in times of need, making strategic alignment and hosting U.S. forces worth their while. But A2/AD capabilities also render forward presence vulnerable, creating a tension between the need to demonstrate U.S. resolve and the need for operationally effective capabilities, which may need to be concealed, dispersed, and positioned further out of range of adversary A2/AD capabilities.
Old Models of Basing Are Insufficient
Prevailing models of basing are likely to prove ill-suited for this contested environment. Historically, the United States has used two distinct approaches to basing: the Cold War and Global War on Terror models. The Cold War model was defined by concentration. To contain the expansion of the Soviet bloc, Washington relied on large bases with substantial numbers of forces in a few key allied countries — most notably West Germany, South Korea, and Japan — around the Soviet periphery.
The challenge with the Cold War model in the present environment is threefold. First, large, concentrated bases are highly vulnerable to being rapidly destroyed by adversary A2/AD capabilities. Though area denial is hardly new, the threats facing U.S. bases today have taken on new significance in light of more accurate and more lethal capabilities; by adversaries’ heavy A2/AD investments to counter the U.S. military asymmetrically; and by the greater relative importance of air and naval power, which are harder to disperse than ground forces, in theaters like the Indo-Pacific and Persian Gulf. Second, deploying large numbers of troops may not be politically sustainable for the United States, particularly in an environment of constrained budgets, or for host governments that have to justify the presence to their constituents. Third, relying on a few central hosts makes Washington dependent on them for access, which could disrupt U.S. power projection if the political opposition in even a single state opposed it.
The Global War on Terror model, in contrast, was defined by dispersion. U.S. basing shifted in response to the rise of diffuse threats posed by transnational terrorism and failed states and the decline of conventional great-power threats after the end of the Cold War. The aftermath of the 9/11 terrorist attacks fueled the shift. Following the Global Defense Posture Review in 2004, the United States relied more on smaller bases (“lily pads”) across wide geographic theaters — from South America to Africa, the Middle East, and Southeast Asia — and reduced its reliance on large, Cold-War style bases. This resulted in troop drawdowns from some longtime base hosts, most notably Germany.
The problems with the Global War on Terror model are the inverse of those of the Cold War model. Though it does not imperil concentrations of equipment or manpower in the same way as the Cold War model, it leaves Washington open to commercial contestation because it relies heavily on countries that are not formal allies or longstanding partners of the United States. In the absence of common security interests, hosts accept U.S. presence for material compensation or to mitigate domestic security concerns. These are risky arrangements that can fall apart in the face of regime change or alternative offers from a competing great power. U.S. access is particularly vulnerable to commercial contestation when Washington relies on material incentives. After all, bids for access can be outbid.
Moreover, while transactional relationships may be sufficient for limited access and a small presence, they may not be if Washington’s goal is instead to find hosts for larger contingents of forces, such as U.S. Navy fleets. Finding hosts that fit all the necessary criteria (e.g., reliable partners, close to an important theater, resilient to adversary A2/AD) is likely to prove challenging. The reported Singaporean reaction to being named as a potential host for a 1st Fleet underscores the complexity of identifying viable and willing hosts.
A New Model of Basing
An alternative model of basing — a “Global Competition” model — would attempt to synthesize the benefits of the Cold War and Global War on Terror models while minimizing their drawbacks to operate effectively in contested environments. To contend with the physical challenges posed by A2/AD, this new, hybrid model seeks to minimize the operational vulnerabilities of the Cold War model by harnessing the flexibility and numbers of the Global War on Terror model. At the same time, this approach aims to minimize reliance on transactional partners that provide access primarily for material or domestic security incentives, recognizing that such relationships are highly vulnerable to commercial and political contestation.
Operationally, this hybrid approach would be based on three principles: hardening, dispersal, and concealment. The physical hardening of U.S. infrastructure should ideally be accompanied by reliance on U.S. and allied air and missile defense systems to blunt adversary A2/AD capabilities. A network of dispersed bases would support a more dispersed, concealed force, increasing the number of targets that adversaries have to account for and making forces more difficult to find. To mitigate the political challenge posed by the optics of repositioning its forces — and to reduce the risk of a fait accompli land grab — the United States could maintain some hardened forward deployments at longstanding bases that can act as “tripwires” and immediate sources of combat support for allies, while at the same time dispersing a larger contingent of forces to serve as reinforcements.
This approach to basing would support emerging strategies of warfare such as the U.S. Navy’s “distributed maritime operations” concept, introduced in 2016, which envisions sea and land cross-domain denial of adversary movement and will require a widely distributed logistics network to implement. The hybrid model would be compatible with operations in other domains too, supporting air operations by increasing the resilience and redundancy of U.S. runways and hangars, while attempting to thread the needle between being sufficiently dispersed and operating within the range of U.S. aircraft.
Strategically, the model would both deepen U.S. ties with traditional partners and build a “large-tent” coalition of like-minded partners wherever it can find them. This approach distinguishes between a spectrum of partners. On one end are partners whose values, interests, and threat perceptions are in lockstep with those of Washington. These are mostly longstanding U.S. formal allies such as Japan, Australia, and the United Kingdom. On the other end are the transactional partners who share neither values nor threat perceptions with the United States but are sometimes willing to grant access in exchange for material benefits.
In the middle is an important range of countries with which the United States does not necessarily have longstanding defense ties but which may wish to partner with Washington out of fear for their own security. These states could include potential U.S. partners like India and Vietnam that are worried about China’s rising clout and assertiveness. Flexible and enhanced access arrangements with these countries can increase the available options in a crisis. Importantly, however, Washington has little ability to influence its partners’ threat perceptions. The particular set of countries that perceive a common threat — and may thus be a reliable source of access — will vary over time. This points to the importance of making the most out of the options that are on offer at any given time.
Taken together, the Global Competition model would in practice have several characteristics. Importantly, it would mean access to facilities in more, or at least different, places, but not necessarily more bases overall. Two-thirds of U.S. overseas sites are concentrated in Germany, Guam, Japan, and South Korea, and only a small fraction of the countries that host U.S. bases are in the crucial Indo-Pacific region. A degree of redundancy and dispersion would ensure that U.S. force posture is resilient to physical and political challenges, meaning the United States may be better served by fewer, physically hardened facilities across more spaces rather than a huge concentration of facilities in a few countries and territories. The emphasis of the Global Competition model would be on flexible arrangements with a smaller presence but with the ability to surge troops when needed. Washington would seek these arrangements with like-minded partners when possible to help harden the U.S. presence to political and commercial contestation.
The Global Competition model may require additional resources, particularly for air and missile defense systems, that are not yet on offer. However, relying on a smaller standing presence at many sites could reduce the model’s costs in funds and manpower. Moreover, shifting some forces from other facilities would allow Washington to move toward the new model while minimizing the amount of new resources that need to be committed — an important consideration in light of likely budgetary limitations.
Realizing the New Model: Recommendations for the Biden Administration
While the specific details of a Global Competition model will vary depending on the theater of operations and operational needs, we can identify three recommendations or principles to help inform the new administration’s planning should it adopt such an approach.
First, the Biden administration will need to tailor strategies to maintain existing security relationships while trying to attract new ones. Targeted defense diplomacy and cooperation can help to secure access arrangements spanning facility use, logistics, and overflight rights. Revitalizing traditional partnerships with formal allies is crucial since these are likely to be the most reliable long-term hosts for U.S. bases.
When it comes to potential partners that may share common security interests, Washington should carefully pursue targeted defense cooperation with each in ways designed to lead to access. This could include military exercises as well as Acquisition and Cross Servicing Agreements, which allow the Defense Department to provide logistic support, supplies, and services directly to partner countries. Doing so is crucial to build confidence in these bilateral relationships and increase potential partners’ trust in the United States to the point where they might be more willing to offer use of their territory and facilities. This kind of tailoring might require revising internal U.S. planning processes, for example by systematically including logistics planners early on in security cooperation or exercise planning.
The Defense Department should also contribute to advancing America’s economic interests. In recent years, Congress has given the department more authority to preferentially award contracts to local firms in host countries. But this authority has not been widely tracked (or even widely used), producing almost no evidence of effectiveness. If these policies work, the United States should consider implementing them proactively in areas where it anticipates economic contestation. If they do not work, Washington should jettison them in favor of new policies that can deliver targeted economic incentives to host communities. Where Washington cannot outbid Beijing, it should act to strengthen partners and help them to withstand economic coercion. Trying to persuade states not to do business with China is likely futile. Instead, a better approach is “empowering them to exploit it.”
Second, the United States needs redundancy in its access and basing options. Redundancies are particularly crucial where partners are less reliable or where authorities are less flexible. Partners that offer the United States use of their territory and facilities may be unwilling to do so in every contingency and may impose limits on the activities Washington can conduct via their facilities. Turkey, for example, refused to allow use of its territory for the U.S. invasion of Iraq in 2003, while most U.S. allies in NATO refused to allow U.S. planes to enter their airspace en route to resupplying Israel during the Yom Kippur War in 1973.
Too often the United States seems to assume that partners will be reliable or that access and overflight authorities will be present unless proven otherwise. A case in point is the belated effort to establish the Northern Distribution Network to cope with Pakistan’s shutdowns of the ground lines of communication on which U.S. forces relied to supply operations in Afghanistan. This default assumption is not tenable in a contested environment. Instead, the Defense Department should assume that ground or sea lines of communication, facilities, and authorities will be vulnerable and should deliberately create back-up options well before crisis erupts.
Redundancy serves an operational purpose as well — namely, to multiply the number of targets an adversary has to contend with while ensuring that U.S. posture is resilient to adversary attacks that would render some portion of bases unusable. This planning principle, however, comes with a price tag. Calling for more dispersed, hardened facilities burdens U.S. air and missile defense forces that are already overstretched and struggling with readiness. If the Biden administration chooses to pursue a hybrid approach, there should be an attendant commitment of resources to augmenting air and missile defense forces. In a resource-constrained environment, this is a choice that may necessitate cuts elsewhere and is thus an inherently difficult political decision.
Finally, the United States needs to think long-term about basing in light of China’s economic and military rise, which presents Washington with its most powerful competitor by far since the Cold War. The stakes for strategic planning are higher in a contested environment, and partnerships and access arrangements should be in place before crisis erupts. The strategic environment has shifted substantially since the 2004 Global Defense Posture Review, suggesting the time is right for a new review. It is also worth keeping in mind that ad hoc basing deals tend to be characterized by frequent renegotiation, which usually favors the host. In Djibouti, for example, the United States negotiated itself out of a relatively cheap, long-term deal for Camp Lemonnier into its current 10-year lease, which is the most expensive in the world.
The United States relies on a network of overseas military bases to project power. Its ability to do so is increasingly contested. These recommendations offer a starting point to dealing with this challenge while recognizing that the path forward will involve difficult political and strategic choices.
Renanah Miles Joyce is a postdoctoral fellow in grand strategy, security, and statecraft at the Massachusetts Institute of Technology and the Harvard Kennedy School.
Brian Blankenship is an assistant professor in the Department of Political Science at the University of Miami and a Stanton Nuclear Security Fellow at the Council on Foreign Relations.