Uncharted Waters: Extended Deterrence and Maritime Disputes

May 01, 2015

by Mira Rapp Hooper

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 “Let me reiterate that our treaty commitment to Japan's security is absolute,” declared President Barack Obama in Tokyo in April 2014. “Article 5 covers all territories under Japan's administration, including the Senkaku Islands,” he continued, referring to the part of the alliance whereby the United States promises to provide military aid to Japan if it is attacked.1 Days later, the President announced a new basing agreement in Manila, affirming Washington's commitment to help “build the Philippines' defense capabilities,” calling it a “vital partner” in maritime security.2 These two presidential statements underscore an increasingly salient set of regional policy quandaries. Maritime and territorial disputes in the Pacific have become prominent in recent years and, when U.S. allies are involved, they present a unique challenge to extended deterrence in the region—one with which Washington is only beginning to grapple.

Although it has relied on extended deterrence since the early Cold War, the United States' so-called “nuclear umbrella” is predominantly designed to deter nuclear and major conventional attacks against the sovereignty and territory of treaty allies. This may, however, have little role to play in deterring conflicts around offshore disputed territories. In recent years, Washington has faced mounting assurance and deterrence challenges because some of its close treaty allies in the Pacific are involved in territorial and maritime disputes, which frequently pit them against a rising China. Rather than fixate on the massive conventional invasions or nuclear attacks that preoccupied U.S. allies during the Cold War, some U.S. allies presently worry that they will not have support if they become involved in a less-than-existential conflict over a disputed island territory or a maritime boundary.

There are at least three reasons why these conflicts present a challenge to U.S. extended deterrence as it has traditionally been practiced. First, existing U.S. treaty commitments themselves do not provide much guidance to adversaries or allies on whether Washington would intervene in a territorial dispute on behalf of an ally, and if it would, under what conditions. Second, where uninhabited islands, rocks, or shoals are at issue, U.S. allies necessarily have a far greater stake in the dispute than the United States itself, making it more difficult for Washington to make its defensive commitments credible. Third, unlike in the Cold War standoff between the United States and Soviet Union, the United States and China are not sworn adversaries. Given its ample incentives to find a modus vivendi with Beijing in other areas, Washington maintains a position of neutrality on most maritime and territorial disputes and does not overtly back its allies' sovereignty claims. China is, however, rising rapidly, and may therefore have both the capability and the will to press its claims against U.S. partners, even as Washington avoids taking sides. Taken together, these challenges combine to mean that allies' fear of abandonment may run especially high when it comes to U.S. alliance commitments around lower- level disputes.

This article proceeds with a brief overview of extended deterrence and assurance in U.S. foreign policy, defining these terms and discussing their role in Cold War strategy. I argue that 21st-century East Asia presents a novel extended deterrence context for the three reasons mentioned above, illustrating why U.S. allies' abandonment fears run especially high with the examples of the Senkaku/ Diaoyu Islands and the U.S.–Japan alliance as well as the Philippines' Spratly Islands claims in the U.S.–Philippines pact. I argue that it is in Washington's interest to address these abandonment fears and remain a committed alliance partner in this new extended deterrence context, recommending a few measures it can take to assuage allies' anxieties while maintaining a working relationship with Beijing.


Extended Deterrence, Past and Present

The United States has relied on extended deterrence, allied assurance, and adversary reassurance as tools of statecraft since the early Cold War.3 Although closely linked, these influence strategies are distinct, so it is useful to begin by defining them. Extended deterrence aims to change the cost calculations of adversaries, specifically by dissuading them from attacking U.S. allies. It seeks to convince potential challengers that an attack on an ally will be met with retaliation by the United States itself. Assurance is a parallel strategy that is directed at allies and seeks to convince them that the United States is committed to their defense. Reassurance, however, is a strategy that aims to convince potential adversaries that they are not going to be the targets of unprovoked, serious harm. It aims in part to convince prospective challengers that extended deterrence is intended to protect allies if they become the victims of attack, but that it will not be used against challengers if they refrain from aggression.4 Thus reassurance is a defensive promise only, not an offensive one. The target of both extended deterrence and reassurance is the potential adversary, while the target of assurance is the ally.

Although they are closely linked, neither extended deterrence nor assurance is a subset of the other. An adversary may be deterred from attacking without the ally being convinced that the adversary will not. Theoretically, the opposite is also true, although less likely. Both extended deterrence and allied assurance are associated with formal security guarantees—positive treaty promises by a major power to provide military aid to an ally if it is the victim of an attack. This analysis will examine U.S. extended deterrence and assurance efforts that are associated with formal security guarantees in East Asia.

Since the early Cold War, the United States has extended deterrence to treaty allies, relying on both nuclear and conventional weapons to do so. While many of the basic contours of deterrence strategy have remained consistent since the early nuclear age, the environment in which the United States extends deterrence today departs from the Cold War context in notable ways. Most Cold War deterrence and assurance efforts were focused on Western Europe and the potential for a massive Soviet conventional or nuclear attack. China was treated as a lesser case. In NATO, the United States and its allies were bound together by a single, multilateral alliance that included hundreds of thousands of forward- deployed U.S. troops, nuclear weapons, and a focus on defending clear front lines. Allies were perennially concerned about whether the United States would make good on its promise to use nuclear weapons on their behalf, but there was no question that if the Soviet Union invaded Europe, Washington would be drawn into the conflict and would meet its treaty obligations to NATO.

Present-day extended deterrence efforts in East Asia diverge from this model in several respects. First, the United States extends deterrence to its allies in the Pacific through a “hub-and-spokes” system—with the United States at the center creating bilateral treaties with regional states—rather than through a cohesive multilateral organization. The depth and breadth of these alliance ties vary significantly within the region: for instance, the United States has over 50,000 military personnel in Japan, and almost none in the Philippines. Deterrence is also geographically distinct today, with no single land border as the focus of defense efforts. Most U.S. allies in East Asia are maritime powers. The U.S. military presence in the region is significant, yet its deterrence efforts are not signaled by a clear front line that is relevant to all of its allies or all potential conflicts in which they might be involved.

Another difference from the Cold War is that multiple potential threats exist in East Asia, rather than just one. While many Pacific nations are concerned about the rise of China, they are also wary of North Korea and the potential for renewed Russian aggression. The nature of most likely conflicts is also distinct from the contingencies that policymakers contemplated during the Cold War. Any future conflict could theoretically escalate into a major conventional or even nuclear exchange, but there is far less reason to fear a deliberate great power war in the region than there was between the United States and Soviet Union. A major ground war on the Korean Peninsula remains a serious concern, but it is difficult to envision a single, massive contingency that would envelop the region—the United States and China each recognize that a major power war would be catastrophic for both.

Most importantly, China and the United States are clearly competitors, but they are not sworn adversaries. Washington therefore has ample incentive to try to reassure Beijing that its alliances do not threaten its security, while at the same time deterring China from taking actions that may be destabilizing and dangerous. In present-day East Asia, extended deterrence commitments and the threats they are intended to address are therefore highly variegated, and in no way zero-sum. This means that the strategies used to deter and reassure China, as well as assure Pacific allies, may be employed in much more subtle and nuanced ways than they have been in the past.

As will be addressed shortly, some longstanding U.S. allies are deeply concerned that they may face limited conventional and sub-conventional conflicts around disputed territories. This environment is clearly preferable to the specter of catastrophic superpower conflict that suffused the Cold War, but complicates extended deterrence. For decades, the United States relied heavily on its nuclear arsenal to dissuade nuclear and major conventional attacks against allies. When the conflicts of concern are at lower levels of escalation, however, it is not clear that these can be deterred using the same means.

This is not to say that nuclear weapons do not play a central role in extended deterrence and assurance in East Asia. Especially since North Korea acquired nuclear weapons, U.S. policymakers have been keenly focused on strengthening extended nuclear deterrence in the region, and have included Pacific allies in nuclear-related consultations to an unprecedented degree.5 Deterrence at high levels of escalation does not necessarily beget deterrence at lower levels, however, and indeed it may invite lower-level opportunism.6 Beyond these big-picture differences between extended deterrence in Europe during the Cold War and extended deterrence in East Asia in the 21st century, however, territorial and maritime conflicts specifically present some novel extended deterrence challenges for the United States.


Extended Deterrence in Dispute

Since the early Cold War, scholars and policymakers have wrestled with obstacles that a major power like the United States faces in making credible deterrent threats on behalf of an ally. While it is quite reasonable to expect that a powerful state would mount a strong response if an adversary attacked its own homeland, extended deterrence requires that the same state convince its adversaries that it will do so on behalf of another state—that is, that it will treat its ally's territory and sovereignty as though it were its own. Such promises may be hard to make credible because they mean that through these defense commitments, the deterrence-extending state may invite retaliation upon itself that it might have otherwise avoided entirely, putting its own territory, citizens, and armed forces at risk.

Existing scholarly research has demonstrated that disputed territory is the most common reason that states wage war.7 Since 1945, Asia has experienced more territorial disputes than any other part of the world. It has also experienced more armed conflict over territory than any other region, and its territorial disputes have been more resistant to settlement.8 It is therefore unsurprising that several U.S. allies in Asia are involved in territorial conflicts, and that they see these as significant security priorities. Where an ally's territorial or maritime conflicts are concerned, however, it is even more difficult than usual for the United States to send credible signals of extended deterrence. There are at least three reasons why this is the case.

First, U.S. security treaties—the written basis of Washington's extended deterrence commitments—are not particularly detailed in their content. These security guarantees generally pledge that the United States will treat an attack on an ally as a threat to its own peace and security, but they do not detail what precisely constitutes an attack, the conditions under which the United States would intervene in a dispute, or the means it would employ in its ally's defense if it did so. This treaty ambiguity serves the purposes of general deterrence, and where many U.S. commitments are concerned, these details need not be put on paper to be understood. Washington's longstanding relationships with Japan and South Korea, for example, make it unthinkable that it could stand aside if Tokyo or Seoul was attacked. Moreover, its significant troop presence on both allies' territory makes it all the more likely that the United States would quickly become involved in conflict if one of these allies was the victim of aggression.

Where an ally has a remote territorial dispute, however, U.S. intervention cannot be so easily presumed. U.S. security treaties generally state that they apply to the ally's home territory, but if a piece of territory is the subject of a sovereignty dispute, there is necessarily some debate as to whether it belongs to the ally at all, and therefore, whether the security guarantee applies there. Washington can, of course, go out of its way to state that its deterrence commitment extends to the territory in contention, as it has done with the Senkaku Islands, but the existence of multiple sovereignty claims injects some additional uncertainty into an already ambiguous treaty promise.

The credibility of deterrence promises may also be strained when the United States and an ally place different value on a territory. Because of its close partnerships, the United States may reasonably assert that it is willing to sacrifice blood and treasure and possibly face ruinous retaliation to defend Tokyo or Seoul. Where an ally's disputed territory is concerned, however, there is far less symmetry of interest. A territorial dispute may invoke the core interests of the claimant states and hold deep symbolic value for that country, but the stakes for a far-off ally like the United States are necessarily diminished. As analysts often note, many of the disputes in the East and South China Seas are over rocky, uninhabited islets, and a pledge to treat these far-off land features as though they were U.S. soil strains belief. Moreover, as scholars Alexander George and Richard Smoke have argued, deterring limited conflicts such as those that may arise over an ally's offshore islands is far more difficult than deterring major wars, as more limited threats are not easy to signal, especially on behalf of an ally.9 Unlike a massive attack on an ally's home territory, a challenger's assault on a far-off island would entail a limited use of military force. For a patron who hopes to deter such an attack, calibrated threats of retaliation are harder to convey.

Finally, as already noted, the United States and China are not locked in a zero-sum standoff as the United States and Soviet Union were during the Cold War. Rather, they compete in some areas and cooperate in others. Washington's desire to maintain a modus vivendi with Beijing helps to explain why it takes a position of neutrality on most sovereignty disputes, including those involving close allies. This balancing act makes good sense, but it adds a third level of complication to U.S. extended deterrence. If Washington remains officially neutral on its allies' territorial disputes, it cannot easily signal an extended deterrence commitment to those territories if it has made one. Strong public statements that the United States intends to defend the disputed territory or clear shows of force in the vicinity hardly signal a neutral position on sovereignty. Moreover, while the United States and China are not sworn adversaries, China is rising rapidly, and this gives it the military capabilities and increasingly the will to advance its sovereignty claims, including those that pit it against U.S. allies. It can therefore employ what Thomas Schelling called “salami tactics”—limited probes of U.S. commitments that aim to advance Chinese interests incrementally and opportunistically without triggering U.S. intervention.

When these factors are combined, they may lead U.S. allies to be especially fearful that their superpower patron will abandon them in conflicts arising from their territorial disputes. States are generally said to abandon an alliance partner if they formally abrogate the alliance treaty, fail to support the ally when the agreement's casus foederis (or case for the alliance) arises, or decline to back a partner in a dispute with an adversary.10 Managing abandonment fears is a central challenge in any alliance. The ambiguous role of allies' territorial disputes in U.S. treaties, the allies' disparate stakes in these disputes, and the United States' need to maintain a relationship with China, however, each inject additional uncertainty into already ambiguous U.S. extended deterrence commitments, and may provoke fears from U.S. allies that they will not have Washington's support if a territorial dispute escalates and pits them against Beijing. Japan's alliance fears over the Senakus Islands in the East China Sea, and the Philippines' territorial claims in the South China Sea illustrate why these factors may elicit unusually high abandonment anxieties from U.S. allies, and why they present a management challenge for extended deterrence and allied assurance.


The Senkakus, South China Sea, and U.S. Alliance Commitments

As China's power-projection capabilities and regional interests have grown in recent years, U.S. allies in East Asia have become increasingly concerned about territorial and maritime disputes in the region. The United States' treaty guarantees with its East Asian allies are longstanding—most date to the early 1950s. Competing sovereignty claims over island territories in the Pacific are also decades old in many cases. China has claimed sovereignty over the Senkaku Islands since the 1970s and Japan has administered them for over a century, with a three-decade break following World War II. The Philippines has claimed features in the Spratly Islands since the 1950s, and China has done so since the 1980s. Only since Beijing has developed the maritime and aerial capabilities which allow it to press its claims, however, have U.S. allies become fearful that small island disputes could bring them into a serious conflict. The conundrum that competing, if long-simmering, sovereignty claims pose for enduring U.S. extended deterrence commitments has therefore only risen to prominence in recent years.

The Senkakus

Since the United States returned the Ryukyu island chain to Japan through the 1972 Okinawa Reversion Treaty, it has maintained that the U.S.–Japan security guarantee applies to the Senkaku Islands.11 This is because Article 5 of the 1960 U.S.–Japan security treaty applies to the “territories under the administration of Japan.”12 China began to voice objections to Japan's authority over the islands in the early 1970s, but has only actively challenged the sea and airspace around the islands in recent years.13 In line with its official neutrality position, however, Washington does not publicly support Japan's sovereignty claims to the Senkakus over China's.

Despite its neutrality on the underlying sovereignty dispute, the United States has reiterated its extended deterrence commitment to Japan when Senkaku tensions have spiked. Following the 2010 diplomatic dispute that arose from the collision of a Chinese trawler and Japanese Coast Guard vessels, Secretary of State Hillary Clinton reaffirmed the U.S. position that the Senkakus fall within the scope of the U.S.–Japan security treaty.14 Shortly after Tokyo purchased three of the five islands in the chain, resulting in another diplomatic row with Beijing in 2012, Assistant Secretary of State Kurt Campbell again reaffirmed that the United States took no position on the underlying sovereignty dispute, but that the Senkakus fell within the scope of the Article 5 commitment in the U.S.–Japan security treaty.15

Outside of specific crises, the United States has actually strengthened its public position on the Senkakus in recent years. In a 2013 statement, Secretary Clinton stated that Washington “would oppose any unilateral action that would seek to undermine Japanese administration” of the Senkakus.16 President Barack Obama restated Clinton's pledge in 2014.17 Nonetheless, the Senkakus still occupy a somewhat uneasy spot in the alliance.

Officials and scholars in Japan have expressed concern that the dual nature of the U.S. Senkaku position—neutrality on the sovereignty dispute, and treaty application via Japan's administration—could undermine Japan if China manages to wrest control of the islands without provoking U.S. military intervention. Some fear that the guarantee may become moot if Beijing executes a fait accompli seizure and takes the islands in a surprise grab. China could also take a different tack, and erode Japanese administration slowly over time through a “creeping invasion.”18 This approach could rely on tactics that may be intended to undermine Japanese control of the islands over time. This includes a unilateral pronouncement by Beijing in 2013 in which it declared an East China Sea Air Defense Identification Zone in an attempt to assert its authority to regulate the airspace over the disputed area. It also includes China's regular Coast Guard incursions into the Senkaku territorial waters, which may be intended to undermine Japanese control.

Particularly if non-military vessels or individuals took the islands, some officials worry that Japan could lose its administrative control without the United States invoking its Article 5 treaty promise. Both a Chinese fait accompli and creeping invasion appear to be included in Clinton's 2013 and Obama's 2014 statements opposing unilateral actions which undermine Japanese administration. Nonetheless, because Japanese officials understand that Japan's national interest in the Senkukus is far greater than the United States', some remain anxious that if their hold on the islands is challenged months or years from now, they may have to go it alone, without the assistance of the U.S. umbrella.

An asymmetry of capabilities compounds this asymmetry of allied stake in the Senkakus sovereignty dispute. Although the Japanese Self-Defense Forces are world class, the U.S.–Japan alliance has historically been unilateral in nature. Japan has only recently raised the defense of the Senkakus to a national strategic priority, and the current U.S.–Japan bilateral defense guidelines, which form the heart of the alliance's strategy and were written in 1997, do not address the possibility of a low-level conflict in the East China Sea.19 So-called “grey zone” conflicts like the Senkakus will presumably be a primary focus as Washington and Tokyo revise these alliance guidelines and as Prime Minister Shinzo Abe moves forward with his revision of Collective Self-Defense in spring 2015.20 At the present time, within the alliance, Japan is responsible for engaging low-level conflicts that may erupt around the Senkakus.21 Tokyo has long maintained a very modest military budget and is only just beginning to acquire some of the capabilities it needs to mount a Senkakus defense.22 It is therefore unsurprising that despite the United States' consistent commitment, Japan remains anxious about what exactly Washington's role would be if the U.S. ally faced an island row with China.

The South China Sea

Washington's position on its treaty commitment to the Senkakus may seem complex and nuanced. The role of U.S. extended deterrence, however, is much more ambiguous when it comes to the Philippines' territorial claims in the South China Sea. The murky nature of this commitment came to light during the 2012 Scarborough Shoals incident, and has resurfaced in several statements that Washington has made since.

On June 15, 2012, the Philippines conceded to China a two-month standoff over Scarborough Reef, a South China Sea land feature that is claimed by China, Taiwan, and the Philippines. During the incident, Chinese vessels trapped Filipino fisherman inside the reef and engaged in economic coercion against the Philippines. As the standoff unfolded, the Philippines sought clarification from the United States about the conditions that would trigger its mutual defense treaty. The United States maintains “strategic ambiguity” on the treaty implications of an outbreak of hostility in the South China Sea— while Washington reaffirmed its security guarantee to the Philippines on multiple occasions during the crisis, it cleaved closely to its neutrality position on sovereignty disputes. It also avoided making any statement on the conditions under which it might enter a conflict in the South China Sea.23

During the Scarborough standoff, the United States acted as a third-party mediator between China and the Philippines, and believed itself to have brokered a deal for mutual withdrawal from the reef, only to watch China move back in and occupy it.24 During these negotiations, China reportedly called its South China Sea claims “core interests,” and refused to open a separate negotiating channel with the Philippines, forcing the talks to become a U.S.–China issue. U.S. officials were therefore cautious to consider the totality of Washington's relationship with Beijing, and in the same press conference in which they reaffirmed their commitment to the Philippines, they also underscored the importance of the U.S.–China dynamic.25 Once they had gained de facto control over the Scarborough reef, Chinese officials reportedly began referring to the “Scarborough Model” of advancing their interests. They also began to speak of strategies of “extended coercion” to pressure allies under the U.S. defense umbrella.26 The United States' limited stakes in the Scarborough Shoal and its desire to maintain a modus vivendi with China meant that it gave circumscribed support to the Philippines.

Since 2012, Washington apparently does not intend to clarify the role of U.S. extended deterrence in the South China Sea or strengthen its support for the Philippines' territorial claims. In 2014, top national security officials called the U.S.–Philippines mutual defense treaty a “rock solid commitment.” In the same statement, however, they made plain that Washington does not see the U.S.– Philippines treaty as applying to the South China Sea the way the U.S.–Japan treaty applies to the Senkakus. The Deputy National Security Advisor referred to a South China Sea conflict as “hypothetical” and refused to speculate on U.S. action in the case of escalation.27 Under the terms of the U.S.–Philippines treaty, Washington reserves the right to intervene following attacks on the Philippines armed forces or vessels, but it has certainly not made a commitment to do so.28 Instead, the United States had made clear that it has an interest in seeing South China Sea disputes resolved through peaceful, legal means, but it has not declared a national interest in any of the Philippines' actual island claims.

The asymmetry of capabilities between the allies heightens this alliance uncertainty. The Philippines has scant naval and coast guard capabilities, and its military is no match for Beijing's.29 Unlike Japan and South Korea, which have long maintained consistently close defense ties to the United States and have robust independent military capabilities, the Philippines is home to no permanent U.S. bases or troops. In April 2014, Washington and Manila signed a defense agreement to allow the United States rotational base access, and the United States has pledged millions of dollars in maritime security aid to its ally.30 The U.S. commitments to help train and equip the Philippines Armed Forces, however, are a long-term project that will take years to bear fruit. Few in Washington or Manila harbor illusions that the Philippines will gain the capacity to defend its own territorial claims any time soon.

Additional U.S. military aid and presence in Southeast Asia may help to assuage some of Manila's most acute abandonment fears. Nonetheless, the fact remains that this U.S. treaty partner faces a much stronger challenger in China. Precisely because it has few hard power options for protecting its interests, the Philippines is now engaged in international arbitration at the Hague against China over its South China Sea claims. Washington has provided some support in this endeavor, including repeated public statements backing the legal process and a State Department research report that may be useful to the Court.31 The arbitration is highly unlikely to settle all of Manila's disputes with Beijing, however. In the meantime, the Philippines' position in the Spratly Islands is far from secure. The Second Thomas Shoal, for example, may be a near-term flashpoint between Manila and Beijing. The Philippines holds the shoal and protects its claim using a rusted-out naval vessel, but China keeps the area surrounded with its own ships. If Manila's vessel slips off the shoal, Beijing will likely move in and take control.32 How U.S. extended deterrence enters this equation, if at all, remains to be seen.


Extending Deterrence Downwards?

These brief case studies of the relationship between U.S. extended deterrence commitments and allies' potential territorial conflicts in the East and South China Seas raise an obvious question: if the United States has limited interests in offshore island disputes and clear reasons to maintain its neutrality position and relationship with China, should it worry at all if its allies are anxious about these potential conflicts? Need it really do more to assuage jittery partners' fears of abandonment around these remote flashpoints?

One reason why Washington should be attentive to the relationship between Japan and the Philippines' sovereignty disputes and its extended deterrence commitments is because of the role assurance plays in any alliance. Extended deterrence is a highly perceptual undertaking, where both allies and adversaries are concerned. The failure to persuade allies that their defense needs are being met at low levels of conflict could conceivably have a deleterious effect on U.S. security guarantees broadly. The belief that U.S. extended deterrence is inoperable at any level of escalation could erode allies' faith in its overall credibility. To remain active and engaged in the region, the United States will need to rely on its forward bases and strong host-nation support—if allies are wary of U.S. support in discrete areas, they may pursue capabilities or policies that may be inimical to these interests.

Another reason why the United States should treat its allies' territorial disputes as an extended deterrence concern is the role that these may play in crisis stability and crisis readiness. U.S. neutrality towards allies' disputes may prove useful for deterrence if a challenger—namely, China—remains reasonably well convinced that the United States may nonetheless intervene on behalf of its partners in the case of war. But if Beijing believes that Washington will likely stand aside in an island row despite its alliance commitments, this may instead invite opportunism and “salami tactics” that test the commitment. Salami tactics will be a less attractive resort if a challenger believes it cannot slice much without provoking a serious response, but if the United States waits to decide whether it will intervene, it may ultimately find itself in a crisis or conflict that it could have avoided.

Additionally, while the United States may not see a clear stake in discrete territorial disputes, it unequivocally has one in the maintenance of the political and territorial status quo in East Asia more broadly defined. No one island feature will tip the balance of power in the Pacific in China's favor, but if Beijing attempted over time to acquire all the land it claims, this would be a strategic game-changer for U.S. partners and Washington itself.

At present, however, it would be unwise for the United States to change its neutrality position on sovereignty disputes and unequivocally bring its allies' claimed territories under the U.S. umbrella. One reason is that doing so may create a moral hazard problem, encouraging allies to press their claims with more confidence. Knowing that they have guaranteed U.S. backing, Tokyo or Manila may grow more assertive in disputes with Beijing than if they expected to bear primary responsibility for the defense of their claims. This, in turn, could cause crisis escalation or conflict that might otherwise have been avoided.

Resource constraints represent a second reason why Washington should not explicitly take on new extended deterrence commitments in the form of its allies' claimed territories. It is no secret that the defense budget is under substantial pressure, and although 60 percent of the U.S. Navy's assets will be in the Pacific by 2020, this does not constitute a radical increase. The number of ships deployed is also expected to shrink under sequestration, and the Navy will struggle to maintain its target number of vessels over the next several decades.33 This raises serious questions about whether or not Washington could reasonably take on new defensive, amphibious roles and missions that it does not already assume. Disputed territories themselves may be no more than rocky islets or submerged reefs, but patrolling the large bodies of water in which they sit is no small task. Taking the lead in comprehensive deterrence and rapid defense missions against maritime challenges may require U.S. resources that are simply unavailable.

The most compelling argument against changing U.S. declaratory policy on allies' disputes, however, is the United States' interest in not alienating Beijing. Washington has been attempting this through a nuanced regional engagement strategy. There are countless areas in which Washington and Beijing can and do cooperate, and great power collaboration will help to mitigate the risk of broader conflict in the region, even if the two also remain competitors. If the United States removes the uncertainty over its role in allies' territorial disputes, it will almost certainly trigger backlash from China. Long-concerned that U.S. alliances constitute efforts to contain it, Chinese officials have also expressed fears that extended deterrence emboldens Washington's allies. Some Chinese strategists have explicitly called on the United States to remove its alliance commitments “from small conflicts” and to “publicly limit extended nuclear deterrence…to existential threats.”34 Beijing may well interpret a declared broadening in the scope of U.S. security guarantees as a direct and serious provocation.

There are clear costs and benefits to the uncertainty over the United States' relationship between its extended deterrence commitment and allies' territorial disputes. A carefully calibrated deterrence policy, however, seeks to protect the status quo while avoiding dangerous, unnecessary security spirals. If one state is determined to revise the status quo and meets little resistance, it may be encouraged to continue pushing the boundaries. If status quo-protecting states do not evince a willingness to use force to protect their interests, the challenger may be emboldened. Even minor conflicts of little intrinsic value may become indices of resolve, requiring firmness to check aggression.35 If, however, the potential challenger is not seriously revisionist but rather predominantly security-seeking, efforts to deter it may be interpreted as direct threats. Policies that are meant only to secure the status quo may result in counteractions by the target that leave all parties worse off.36

Put differently, the United States faces clear tradeoffs in strengthening extended deterrence and allied assurance on one hand, and reassuring China on the other. U.S. policymakers do not and cannot know whether China will pursue a systematically revisionist strategy in the future. China has displayed tendencies toward “moderate revisionism,” and only time will tell whether Beijing will press all of its expansive Pacific claims.37 Simultaneously, China has also taken some important if modest steps to encourage maritime stability, such as agreeing to military-to-military confidence-building measures with the United States in late 2014, and an East China Sea crisis mechanism with Japan in 2015. If these efforts do not bear fruit and China appears to be systematically employing coercion toward U.S. allies around disputed territories, Washington may want to rethink its neutrality position, and should at least state publicly that it retains the right to do so in response to bad behavior by Beijing. For the time being, however, the United States must find ways to engage its allies' abandonment fears in the East and South China Seas without compromising reassurance efforts towards China.


Navigating Uncharted Waters

As long as the United States pursues a China strategy that relies on reassurance, it should try to assuage allies' abandonment fears through policies that focus on bolstering assurance within the alliance itself, as opposed to efforts that explicitly aim to ratchet up deterrent threats. There are a few intra-alliance measures that Washington can take to bolster assurance around island disputes without alienating Beijing.

The United States is already engaged in significant efforts to help allies and partners boost their own capacity to deter and defend in potential island contingencies. It should continue to help train and equip countries like the Philippines, and should encourage other states in the region to do the same. It should also invest in coast-guard-to-coast-guard efforts and focus on helping partners build their maritime domain awareness capabilities. The better allies' coast guards are able to engage these island hotspots, and the more they can monitor events at sea, the less likely accidental or inadvertent escalation is to occur. China makes ample use of its non-military maritime law enforcement capacity, and the United States and its allies can do the same. Training allies to use and maintain new systems is as important as the defense equipment itself. Partner capacity-building efforts are, however, long projects and will take years to bear fruit. In the nearer term, Washington can take some additional, concrete steps to assuage allies' abandonment fears around these flashpoints.

First, Washington should continue to strengthen peacetime consultation efforts in all of its Pacific alliances. Even if some ambiguity remains in the public U.S. positions on maritime disputes, it is vital that allies share a common understanding of each nation's responsibilities when crises occur. Washington and its East Asian allies maintain numerous and highly productive strategic dialogues. These may, however, be segmented across the conflict spectrum. The Extended Deterrence Dialogue with Japan and Extended Deterrence Policy Committee with South Korea, for example, are important initiatives that focus on strategic deterrence, but do not deal with lower-level crises or how these might escalate into wider war. Washington should consider the integration of some of its strategic dialogues, so that allies have a unified understanding of how minor conflicts may escalate and where off-ramps may exist. The United States may also want to form a conventional extended deterrence consultation mechanism with the Philippines, modeled off those it holds with the ROK and Japan. This would complement its ongoing military assistance and capacity- building efforts with Manila.

Second and relatedly, Washington should consider establishing standing bilateral crisis bodies with both Japan and the Philippines to ensure operational coordination if island disputes begin to escalate. Of the United States' East Asian partners, only South Korea maintains a standing, combined military command with the United States. The U.S.–Japan alliance does have a Bilateral Coordination Mechanism, but only a major armed attack can trigger it, and thus it has never actually been activated. In contrast, the U.S.–Philippines alliance has few standing alliance institutions at all and no crisis mechanism whatsoever. By establishing standing crisis bodies, the United States and its allies can promote steady-state readiness around disputed territories, even if Washington does not publicly commit itself to allies' sovereignty claims. Washington's commitment to intervene militarily in a crisis in the East or South China Seas may remain contingent or probabilistic, but it can still help its allies prepare to manage these flashpoints, and it can promote crisis readiness within the alliance if escalation occurs.

Without requiring an overhaul in the way Washington thinks about extended deterrence, these intra-alliance prescriptions may improve coordination, mollify allies' abandonment anxiety, and send the message to potential challengers that U.S. partners are not alone when they are targeted around sovereignty disputes. Integrated alliance dialogues and bilateral crisis coordination mechanisms are appropriate measures whatever Beijing's long-term intentions are in the East and South China Seas.

During the implementation of these intra- alliance measures, Washington should take care to emphasize its defensive objectives. The United States and China still need to move forward on defense transparency efforts and military-to- military ties, and none of these assurance initiatives should prevent that from occurring.38 If, however, Beijing persistently resorts to coercion, more overt deterrent measures may be necessary. In addition to publicly announcing its support for allies' sovereignty claims (revealing its intent to help defend them), the United States may take a number of measures in concert with its allies to send stronger signals of capability to do so. The United States and its allies may need to conduct military exercises near or in disputed areas, or more regularly and publicly practice the defense and retaking of maritime territories.

In crafting an approach to extended deterrence and assurance around disputed territories, Washington has a menu of options from which to choose. Measures that emphasize intra-alliance coordination and readiness can provide assurance and reinforce deterrence without undermining efforts to reassure Beijing. If, down the road, China appears to be systematically using coercion, consistently frustrating efforts at confidence building, then bringing allies' territorial disputes under the U.S. security umbrella may make strategic sense. The balance between extended deterrence, assurance, and reassurance will almost certainly need to be revisited and recalibrated in the years to come.



The United States can manage its uneasy relationship between extended deterrence and assurance around its allies' disputes, but must balance this with the need to maintain reassurance to and a working relationship with China. In the near term, Washington can bolster allied assurance and deterrence around disputed territories through several intra-alliance mechanisms, and shift to a firmer deterrence policy if it judges that Beijing's use of coercion against its allies has become chronic.

The novel nature of this lower-level deterrence problem, however, highlights a larger point. The United States and the Soviet Union only began to extend deterrence to allies in the early Cold War. When they did, each gave security guarantees to states that were already in or associated with clear spheres of influence, in an international environment that was often judged to be zero- sum. Many of the extended deterrence tools of the past, including large conventional troop deployments and nuclear declaratory policies, may not be finely tuned enough to engage either potential conflicts around island disputes or a potential challenger who is not a full-blown adversary. The extended deterrence and assurance efforts of the future will have to be uniquely nimble and nuanced, with an eye to reassuring challengers like China as well as assuring and deterring on behalf of allies along the way.

It is also worth noting that history has never seen one superpower rise in a region in which another had a dense system of long-standing alliances. Security guarantees are, first and foremost, tools for protecting the territorial status quo. But when a major power is on the ascent, its conceptions of what constitutes the status quo may differ fundamentally from those of the dominant state.39 Maritime and territorial disputes are just one particularly prominent example of this fact.

In addition to the task of carefully calibrating its extended deterrence and assurance policy, policymakers in Washington therefore face greater and more abstract challenges. Beyond any particular sovereignty dispute, how will they define the status quo that is to be protected, and what will constitute an unacceptable infringement upon it? How will they communicate this defensive delineation to Beijing or others, without provoking destabilizing enmity? Extended deterrence has been an incredibly successful tool of U.S. foreign policy, but like all influence strategies, it is a means to an end. The puzzles that plague the uneasy relationship between territorial disputes and U.S. extended deterrence as well as assurance today can only be solved by broader strategies that reinforce U.S. interests and bring security to this vital region.


1.         Office of the Press Secretary, The White House, “Press Conference by Obama, Japanese PM Abe,” in Tokyo, April 24, 2014, http://iipdigital.usembassy.gov/st/english/ texttrans/2014/04/20140424298237.html#ixzz30J147bNS.

2.         “Full Transcript of the Remarks of the Remarks of President Aquino and President Obama in their Joint Press Conference,” GMA News, April 28, 2014, http://www. gmanetwork.com/news/story/358751/news/nation/full-transcript-of-the-remarks-of-pre sident-aquino-and-president-obama-in-their-joint-press-conference.

3.         This section is adapted in part from: Linton Brooks and Mira Rapp-Hooper, “Extended Deterrence, Assurance, and Reassurance during the Second Nuclear Age,” in Strategic Asia 2013–2014: Asia in the Second Nuclear Age, Ashley J. Tellis, Abraham M. Denmark and Travis Tanner, eds. (National Bureau for Asian Research, October 2013), pp. 270277.

4.         Jeffrey W. Knopf, “Security Assurances: Initial Hypotheses,” in Security Assurances and Nuclear Nonproliferation, ed. Jeffrey W. Knopf (Stanford: Stanford University Press, 2012), pp. 1416.

5.         The 2010 Nuclear Posture Review called for the “strengthening” of extended deterrence on the regional level with emphasis on North East Asia. Nuclear Posture Review Report (Department of Defense, April 2010), http://www.defense.gov/npr/docs/ 2010%20Nuclear%20Posture%20Review%20Report.pdf.

6.         Glenn Herald Snyder, The Balance of Power and the Balance of Terror (San Francisco: Chandler, 1965). Robert Rauchhaus, “Evaluating the Nuclear Peace Hypothesis
A Quantitative Approach,” Journal of Conflict Resolution 53, no. 2 (2009): 258277.

7.         John A. Vasquez, The War Puzzle (New York: Cambridge University Press, 1993).

8.         Taylor M. Fravel, “Territorial and Maritime Boundary Disputes in Asia,” in Oxford Handbook of the International Relations in Asia, Saadia M. Pekkanen, John Ravenhill, and Rosemary Foot, eds., (New York: Oxford University Press, 2014), chapter 27.

9.         Alexander L. George and Richard Smoke, Deterrence in American Foreign Policy: Theory and Practice (New York: Columbia University Press, 1974), p. 2.

10.       Glenn H. Snyder, Alliance Politics (Ithaca: Cornell University Press, 1997), p. 182.

11.       Mark E. Manyin, Senkaku (Diaoyu/Diaoyutai) Islands Dispute: U.S. Treaty Obligations (CRS Report No. R42761) (Washington, DC: Congressional Research Service, January 22, 2013), p. 4, www.fas.org/sgp/crs/row/R42761.pdf.

12.       Ministry of Foreign Affairs of Japan, “1960 Treaty of Mutual Cooperation and Security Between Japan and the United States of America,” http://www.mofa.go.jp/region/n- america/us/q&a/ref/1.html.

13.       Manyin, Senkaku (Diaoyu/Diaoyutai) Islands Dispute: U.S. Treaty Obligations, p. 1.

14.       U.S. Department of State, “Joint Press Availability with Japanese Foreign Minister Seiji Mehara,” speech by Hillary Rodham Clinton, in Honolulu, Hawaii, October 27, 2010, http://m.state.gov/md150110.htm.

15.       Maritime Territorial Disputes and Sovereignty Issues in Asia: Hearing before the Subcommittee on East Asian and Pacific Affairs of the Committee on Foreign Relations, 112th Cong., 2 (September 20, 2012) (statement of Kurt Campbell, Assistant Secretary of State), http://www.gpo.gov/fdsys/pkg/CHRG-112shrg76697/ html/CHRG-112shrg76697.htm.

16.       U.S. Department of State, “Remarks with Japanese Foreign Minister Fumio Kishida after their Meeting,” speech by Hillary Rodham Clinton, in Washington, DC, January 18, 2013, http://www.state.gov/secretary/20092013clinton/rm/2013/01/203050.htm.

17.       Office of the Press Secretary, The White House, “Press Conference by Obama, Japanese PM Abe,” in Tokyo, April 24, 2014, http://iipdigital.usembassy.gov/st/english/ texttrans/2014/04/20140424298237.html#axzz30DVXhFDm.

18.       Sugio Takahashi, “Upgrading Japan-US Defense Guidelines: Toward a New Phase of Operational Coordination,” Project 2049 Institute, 2013, pp. 78, http://project2049. net/documents/japan_us_defense_guidelines_takahashi.pdf.

19.       “Guidelines for Japan–U.S. Defense Cooperation,” Ministry of Foreign Affairs of Japan, 1997, http://www.mofa.go.jp/region/n-america/us/security/guideline2.html.

20.       “Abe Circles 1959 Top Court Ruling to Justify Collective Self Defense,” April 16, 2014, Japan Times, www.japantimes.co.jp/news/2014/04/16/national/government-to- cite-past-ruling-to-justify-exercise-of-collective-self-defense/#.U1BEQMcoxTU.

21.       Takahashi, “Upgrading Japan-US Defense Guidelines,” p. 8.

22.       “Japan Approves Record 4.98 Trillion Yen Defense Budget,” January 13, 2015, BBC News Asia, http://www.bbc.com/news/world-asia-30808685.

23.       U.S. Department of State, “Remarks with Secretary of Defense Leon Panetta, Philippines Foreign Secretary Albert Del Rosario, and Philippines Defense Secretary Voltaire Gazmin After Their Meeting,” speech by Hillary Rodham Clinton, in Washington DC, April 30, 2012, http://www.state.gov/secretary/20092013clinton/rm/ 2012/04/188982.htm; Office of the Press Secretary, The White House, “Remarks by President Obama and President Aquino of the Philippines after Bilateral Meeting,” in the Oval Office, Washington DC, June 8, 2012, http://www.whitehouse.gov/the-press- office/2012/06/08/remarks-president-obama-and-president-aquino-philippines-after- bilateral.

24.       Ely Ratner, “Learning the Lessons of Scarborough Reef,” The National Interest, November 21, 2013, http://nationalinterest.org/commentary/learning-the-lessons- scarborough-reef-9442.

25.       U.S. Department of State, “Remarks with Secretary of Defense Leon Panetta, Philippines Foreign Secretary Albert Del Rosario, and Philippines Defense Secretary Voltaire Gazmin After Their Meeting,” speech by Hillary Rodham Clinton, in Washington DC, April 30, 2012, http://www.state.gov/secretary/20092013clinton/rm/ 2012/04/188982.htm.

26.       Ely Ratner, “Learning the Lessons of Scarborough Reef,” November 21, 2013, The National Interest, http://nationalinterest.org/commentary/learning-the-lessons-scarbor ough-reef-9442.

27.       Office of the Press Secretary, The White House, “Press Briefing by Deputy National Security Advisor for Strategic Communication Ben Rhodes and NSC Senior Director for Asian Affairs Evan Medeiros,” in Kuala Lampur, Malaysia, April 27, 2014, http:// www.whitehouse.gov/the-press-office/2014/04/27/press-briefing-deputy-national-security- advisor-strategic-communication-.

28.       “Mutual Defense Treaty between the United States and the Republic of the Philippines,” The Avalon Project, Lillian Goldman Law Library, Yale Law School, August 30, 1951, http://avalon.law.yale.edu/20th_century/phil001.asp.

29.       “Philippines Military Strength,” Global Firepower, March 27, 2014, http://www. globalfirepower.com/country-military-strength-detail.asp?country_id=philippines.

30.       Keith Bradsher, “U.S. Forging Closer Military Ties with Philippines,” The New York Times, December 17, 2013, http://www.nytimes.com/2013/12/18/world/asia/us-forging- closer-military-ties-with-philippines.html?_r=0.

31.       U.S. Department of State, Bureau of Oceans and International Environment and Scientific Affairs, Office of Ocean and Polar Affairs, “China: Maritime Claims in the South China Sea,” Limits in the Seas no. 143, , December 5, 2014, http://www.state. gov/documents/organization/234936.pdf.

32.       Jeff Himmelman, “A Game of Shark and Minnow,” New York Times Magazine, October 27, 2013, http://www.nytimes.com/newsgraphics/2013/10/27/south-china-sea/.

33.       Ronald O'Rourke, Navy Force Structure and Shipbuilding Plans: Background and Issues for Congress, (CRS Report No. RL32665) (Washington, DC: Congressional Research Service, August 1, 2014), http://fas.org/sgp/crs/weapons/RL32665.pdf.

34.       Li Bin and He Yun, “Credible Limitations: U.S. Extended Nuclear Deterrence and Stability in Northeast Asia,” in Disarming Doubt: The Future of Extended Nuclear Deterrence in East Asia, Rory Medcalf and Fiona Cunningham, eds. (Woollahra: Longueville Media, 2012), pp. 61–68.

35.       Robert Jervis, Perception and Misperception in International Politics (Princeton: Princeton University Press, 1976), pp. 5862.

36.       Ibid., pp. 6267.

37.       Ronald O'Rourke, Maritime Territorial and Exclusive Economic Zone (EEZ) Disputes Involving China (CRS Report No. R42784) (Washington, DC: December 24, 2014),
pp. 811, http://fas.org/sgp/crs/row/R42784.pdf.

38.       For specific proposals to this effect, see: James Steinberg and Michael E. O'Hanlon, Strategic Reassurance and Resolve: U.S.–China Relations in the 21st Century (Princeton: Princeton University Press, 2014), Appendix A.

39.       See Mira Rapp-Hooper and Zachary Cooper, “A New Model of Great Power Transitions?: Extended Deterrence and U.S.–China Relations,” presented at the American Political Science Association Annual Meetings, August 30, 2014.