Introduction: The defence diplomacy paradox

After the Malaysian Airlines flight MH370 disappeared on 8 March 2014, a search and rescue (SAR) operation was started that grew within a week to include a ‘total of 57 ships and 48 aircraft from 13 countries’ deployed across a search area that extended from the South China Sea to the Indian Ocean.Footnote ¹ At first glance, this SAR comprising more than a hundred platforms from over a dozen different states appears to be the epitome of defence diplomacy. Andrew Cottey and Anthony Forster, in their genre-defining entry to The Adelphi Papers series, define defence diplomacy as ‘the peacetime cooperative use of armed forces and related infrastructure (primarily defence ministries) as a tool of foreign and security policy’.Footnote ² Defence diplomacy is thus a long list of activities that focus on the non-coercive interaction between militaries, such as military exchanges and exercises, peacekeeping, or SAR operations. However, applying a more critical lens to the MH370 SAR presents a much more complicated picture of the states involved in the search as jockeying for influence and positioning themselves as more capable than others. This included China's criticism of Malaysia's handling of the search, especially after Malaysia finally declared on 15 March 2014 that MH370 had flown on for hours after disappearing off the radar, which meant that the previous search efforts focused upon the South China Sea had been pointless. China thereby deployed more assets in the subsequent south Indian Ocean search to demonstrate its capabilities and responsibilities over those of Malaysia's.Footnote ³ China also delayed its loan of pandas to Malaysia – so-called ‘panda diplomacy’ – due to its unhappiness with Malaysia over how the search had been handled.Footnote ⁴ This article argues that cases like the MH370 SAR are hardly exceptional with regard to defence diplomacy.

Whereas defence diplomacy is usually promoted as a cooperative activity to build trust and confidence between states, thus beneficially shaping the environment in which foreign policy is made, we contend also the opposite. To begin with, defence diplomacy contains realpolitik motivations with regard to the demonstration of military power. Hence, it is as much about competition with each other as it is about cooperation. Specifically, states compete in terms of secrecy, swaggering, and shows of force during defence diplomacy, ‘the three main schools of thought on the role that military forces and military activities can play in shaping perceptions of power’.Footnote ⁵ The metaphor drawn here is hence that defence diplomacy is akin to fists clenched in competition, albeit clothed in soft velvet, the veneer of cooperation. Consequently, even as the cooperative aspect of defence diplomacy reinforces strategic trust – predictability or credibility; its competitive aspect weakens moralistic trust – the belief about the good intentions of others, thus adversely shaping the foreign policy environment.Footnote ⁶ Defence diplomacy therefore represents a notable paradox: between competition and cooperation, and between promoting strategic trust while harming moralistic trust. We test and demonstrate our novel argument about this ‘dark’ side of defence diplomacy through a case study of institutionalised regional peacekeeping in Southeast Asia, or rather, the lack thereof. Southeast Asia is arguably contemporary defence diplomacy's region par excellence. Today, the ‘impressive number of ASEAN defence-related meetings, conferences and activities taking place on a multilateral basis reflects a surprising high degree of institutionalisation’ of defence diplomacy.Footnote ⁷

The argument presented herein is different from previous studies about the negative and mostly unintended side effects of defence diplomacy. Examples such as the increased likelihood of a coup d’état as a consequence of military assistance or exchanges, or abuses during peacekeeping missions, document defence diplomacy's ‘dark side’ as it plays out mostly domestically.Footnote ⁸ Our argument, however, scrutinises the intended, competitive goals of defence diplomacy and shows how this can affect its cooperative objectives at the international level between states.

The remainder of this article is divided into three main sections. The first section presents a literature review of defence diplomacy, highlighting a gap in the literature about how exactly defence diplomacy is supposed to work. We consequently propose the mechanism of ‘regimes’ therein. The section also examines the relationship between defence diplomacy and trust, strategic and moralistic, and how this trust interacts with regimes. The second section then develops our theoretical argument on how defence diplomacy furthers competition in terms of shows of force, swaggering, and secrecy, and how defence diplomacy thereby erodes moralistic trust between states due to this competitive aspect. The third section lays out our case study. It begins by analysing the state of defence diplomacy in Southeast Asia to set the context for the case. We subsequently demonstrate our argument based on the multilateral relations arising from the area of peacekeeping, a policy field that has figured prominently on Southeast Asia's defence diplomacy agenda, before the article is concluded.

How defence diplomacy works: Regimes of trust

The origins of defence diplomacy are commonly traced to post-Cold War Europe, where policymakers sought to build trust between former rivals and socialise the former communist nations into adopting a democratic model of civil-military relations.Footnote ⁹ The concept was further refined in the United Kingdom's 1998 Strategic Defence Review, which defined defence diplomacy as one of eight core missions of the armed forces with the goal to ‘dispel hostility, build and maintain trust and assist in the development of democratically accountable armed forces, thereby making a significant contribution to conflict prevention and resolution’.Footnote ¹⁰ Cottey and Forster subsequently provide a list of defence diplomacy activities, which include: exchanges between military officers or civilian defence officials, appointing defence attachés to other states, agreements on military cooperation, the training of foreign personnel, providing aid in the form of military equipment or other goods, or training exercises between militaries, among others. Including not only friendly states but also potential rivals and former enemies, these demonstrate the ‘key shift’ from defence cooperation's ‘longstanding realpolitik role of supporting the armed forces and security of allies’ to a ‘means of pursuing wider foreign and security policy goals’.Footnote ¹¹

Other definitions similarly highlight the cooperative use of the military instrument and the positive effects of defence diplomacy on a state's foreign relations.Footnote ¹² Hence, from ‘the traditional conceptualization of militaries in its coercive use of force and its associated functions of defense, deterrence, compellence, and swaggering’, militaries instead took on a non-traditional, diplomatic role, resulting in the somewhat oxymoronic concept of ‘defence diplomacy’, or ‘military diplomacy’, to the extent that today, the typical focus of defence diplomacy is on the latter half of the term and not the former.Footnote ¹³

In this usual cooperative paradigm of defence diplomacy, three conventional roles can be identified.Footnote ¹⁴ First, under the dominant orthodoxy of the post-Cold War model, defence diplomacy enables good governance in terms of civil-military relations as the exchange with democratic armed forces helps democratising states in transition establish objective civilian control of the military.Footnote ¹⁵ Second, defence diplomacy is believed to build trust and confidence, to the extent that conflicts and crises can be handled peacefully if they arise. For instance, then Second Minister for Defence for Singapore, Chan Chun Sing, himself a former major-general, in a 2014 speech to military officers engaged in the annual Asia-Pacific Programme for Senior Military Officers (APPSMO) – a regional defence diplomacy summer camp held in the city-state – remarked that the ‘job of the military is to preempt crises and not just manage crises’, particularly since the ‘military community has the unique advantage of growing up together and knowing each other for many years, often for more than the number of years that political leaders get to know each other’ such that ‘these established links’ could ‘provide added channels of communication for the political masters’ to help ‘reduce misunderstanding’.Footnote ¹⁶ Third, and in a related manner, defence diplomacy supports wider foreign policy goals. For example, providing humanitarian assistance and disaster relief (HADR) aid helps build better relations between the donor and recipient states. Accordingly, in 2005, an Indonesian poll found that 65 per cent of Indonesians had a favourable image of the US due to its relief efforts in the 2004 Boxing Day tsunami, while in the same year, opposition to the US-led war on terror declined from 72 per cent to 36 per cent.Footnote ¹⁷

Central to all three roles of defence diplomacy is the idea that it helps to build trust beyond the specific defence diplomacy activity itself. The concept of trust has been implicitly studied in the traditional international relations and strategic studies literature. Most importantly, it is mistrust under the state of anarchy that leads to the security dilemma and for states to rely on self-help.Footnote ¹⁸ In comparison however, the explicit study of trust in the discipline is much more recent.Footnote ¹⁹ Drawing on insights from social psychology, two main types of trust can be identified: strategic trust and moralistic trust. Strategic trust is a calculation (predictability) and expectation (credibility) about another's behaviour in a specific situation; while moralistic trust is the general ‘belief that others share your fundamental moral values and therefore should be treated as you would wish to be treated by them’ (good intentions).Footnote ²⁰ The former is a more rationalist type of trust that may be enforced via oversight and sanctioning mechanisms, but the latter moralistic trust is understood as a phenomenon with social and psychological dimensions involving how actors perceive and identify with others. Moralistic trust is thus closer to what we understand by being ‘trustworthy’ in layman's terms, a normative bond between the actors.Footnote ²¹ For example, even as the US and the former USSR cooperated in instances like the 1988 Intermediate-Range Nuclear Forces Treaty during the Cold War, such did not indicate that either found the other trustworthy. Defence diplomacy is typically meant to extend both types of trust. Through greater predictability, credibility, and trustworthiness, cooperating states reduce uncertainties, misunderstandings, and even perceived vulnerabilities, independent of any particular situation or policy area.

However, the extant literature on defence diplomacy has largely failed to specify the mechanisms by which defence diplomacy actually grows trust. The prevailing assumption is simply that defence diplomacy works; that is, it fosters cooperation and prevents conflict.Footnote ²² For example, whereas Cottey and Forster highlight the role of realist ‘international realpolitik’ in the historical ‘military cooperation and assistance’ that predated the cooperative use of the armed forces in defence diplomacy, they simply refer to ‘strategic engagement’ of ‘former or potential enemies’ in the ‘newer’ defence diplomacy, without specifying how the behavioural dynamics of enmity might be overcome.Footnote ²³ Similarly, in a special issue on defence diplomacy in Southeast Asia, the editors define defence diplomacy as referring ‘to the collective application of pacific and/or cooperative initiatives by national defense establishments and military practitioners for confidence building, trust creation, conflict prevention, and/or conflict resolution’.Footnote ²⁴ Yet, they do not stipulate exactly how confidence is built, trust created, and conflicts prevented or resolved. Gregory Winger is thus correct when he concludes that ‘existing definitions of defence diplomacy either describe what it looks like (peaceful use of military force) or what it hopes to achieve (cooperation and conflict prevention) without explaining what defence diplomacy actually is’.Footnote ²⁵

Within the literature, only two explanations are proffered for the means of defence diplomacy, albeit unsatisfactorily. The first is the ‘intuitively attractive’ idea that security problems between states are best dealt with by the armed forces, since ‘plain-speaking military men, talking soldier to soldier, can resolve differences and build trust and understanding where civilian diplomats and politicians become mired in half-truths, evasions and circumlocutions’.Footnote ²⁶ Fundamentally, such ‘instinctive solider-to-soldier trust’ exaggerates a ‘common bond’ between members of the military trained to fight each other while further calling into question how non-uniform personnel in the defence establishments do defence diplomacy. The second explanation is Winger's suggestion that militaries exercise soft power in defence diplomacy activities so that through ‘the peaceful use of the defense institutions of one country’, the ‘government institutions of another country’ are co-opted ‘in order to achieve a preferred outcome’.Footnote ²⁷ Yet, soft power – the power to attract as opposed to the coercive nature of hard power – is insufficient to explain the workings of defence diplomacy.Footnote ²⁸ Soft power can possibly account for the achievement of some wider foreign policy goals and the democratising roles of defence diplomacy, but is unable to explain, by itself, how trust is built, especially how it transfers from the defence establishment to other government institutions, or how it translates from bilateral ties to the multilateral level.

We therefore propose that defence diplomacy should be seen as building up specific norms and regimes of security cooperation, thereby strengthening strategic and moralistic trust as these regimes consolidate. Regimes, according to Stephen Krasner's widely used definition, are ‘sets of implicit or explicit principles, norms, rules, and decision-making procedures around which actors’ expectations converge in a given area of international relations’.Footnote ²⁹ Such regimes of security cooperation affect both the rationalist calculations of strategic trust as well as the social and psychological bases of moralistic trust. As these regimes proliferate through more cooperative defence diplomacy activities, greater strategic and moralistic trust is built; a virtuous cycle. Behaviours become more predictable and credible, while common values, identity, and empathy are established, enabling the three conventional roles of defence diplomacy. Moralistic trust, in particular, allows trust to transcend the temporal and spatial dimensions. It facilitates ‘the diffuse reciprocity often necessary for long-term cooperation’, transfers ‘to other potential areas of mutual benefit in a way that is not possible’ with rationalist strategic trust, including beyond the defence establishment, and also enables even outsiders to be included.Footnote ³⁰ Conversely, defence diplomacy falls short of its goals when either strategic or moralistic trust does not increase.

In recent years, a number of studies have questioned whether defence diplomacy actually achieves, or can even achieve, its desired results.Footnote ³¹ Daniel Baldino and Andrew Carr, for example, probe whether Australian defence diplomacy has led to ‘“strategic” persuasion’ and found that no such transformative effects have occurred, despite positive outcomes at the tactical and operational levels.Footnote ³² A particularly convincing case they disproved was Australia's 1999 intervention in East Timor, then part of Indonesia. This intervention has often been celebrated as a strategic win due to the long-established defence diplomacy ties between the Australian and the Indonesian militaries, which was thought to have enabled the intervention to be carried out in Indonesia without conflict.Footnote ³³ However, as Baldino and Carr highlight, other important factors leading to the Indonesian strategic decision to accept the intervention include realpolitik considerations such as ‘the intensified military posturing and the sustained external political pressure on Indonesia during the crisis’, from the UN, the US, and the Australian government. Rather than the history of defence diplomacy ties between Australia and Indonesia building trust between the two states, these ties did no more than to smooth ‘the specific organisational challenges of the arrival’.Footnote ³⁴

However, in general, studies shedding a critical light on the effectiveness of defence diplomacy are often policy-oriented and thus tend to concentrate on its benign effects. Hence, their ultimate conclusion is somewhat akin to the philosophical ‘Pascal's wager’ in that although the beneficial trust-building effects of defence diplomacy are uncertain or can fail, there is still nothing to lose from doing defence diplomacy.Footnote ³⁵ Such a narrow focus of attention on defence diplomacy's cooperative and trust-building roles with the corollary of exhibiting only limited theoretical curiosity about any potential unintended strategic consequences is surprising insofar as defence diplomacy's deterrent and competitive elements, particularly towards external parties, are well known. Beatrice Heuser and Harold Simpson, for instance, note that joint military exercises, a chief activity from the defence diplomacy portfolio, are aimed, among other things, at deterring enemies even though the very word ‘deterrence’ does not usually figure in defence policy guidelines.Footnote ³⁶ The literature on defence diplomacy in Southeast Asia also provides numerous examples of its realpolitik elements. Pankaj Kumar Jha, for example, argues that India's defence diplomacy in the Southeast Asian region has of late pursued a China containment strategy.Footnote ³⁷ Capie contends that even HADR ‘advances core goals related to traditional defense missions’.Footnote ³⁸ Nevertheless, apart from such mostly ad hoc observations, explicit attention has not been focused upon the internal competitive aspect of defence diplomacy directed towards those militaries partaking of it.Footnote ³⁹ Hence, building on these limited insights, the next section sets forth our argument on how defence diplomacy is simultaneously cooperative and competitive and how this can generate negative effects.

The dark side: Diplomatic defence

On the most basic level, defence diplomacy activities are demonstrations of military capabilities, of which there are three main perspectives. The first holds that such demonstrations are ‘shows of force’. Although they may sometimes serve to showcase military power per se, these are usually intended to signal interest or resolve during bargaining or crisis situations.Footnote ⁴⁰ An example of such coercive diplomacy was former US President Bill Clinton sending two aircraft carrier battle groups into East Asia during the Taiwan Strait crisis in 1996 to demonstrate US resolve to China. Second, states may exhibit their military capabilities for the purpose of ‘swaggering’, the idea that these capabilities serve to bolster pride in and of a state or its people.Footnote ⁴¹ This could be observed in the 2019 US Independence Day ‘spectacle’ in Washington, which involved a grandiose military display of tanks and aircraft mocked as ‘a kind of Trump-branded rally’.Footnote ⁴² The third view on demonstrations of military capabilities holds that states are likely to enforce ‘secrecy’ and downplay their capabilities so as to maintain the advantage of surprise for when kinetic force is actually required.Footnote ⁴³ China today, for example, has often been criticised for maintaining secrecy with regard to its military modernisation and its under-reported military budget.Footnote ⁴⁴ These three areas are where states compete when engaged in defence diplomacy with each other: shows of force, swaggering, and secrecy.

Before describing each of them in detail, it is worth noting that by definition, such competition can neither be the sole nor overriding purpose of a specific defence diplomacy activity. In accordance with the characterisations presented earlier, defence diplomacy's principal goal is the exercise of positive influence onto a state's security environment. If such motivation were absent, it is pointless to speak of defence diplomacy. Rather, we contend that defence diplomacy is pursued for multiple purposes at the same time, with both cooperative and competitive benefits from the same activity. In this way, defence diplomacy is as much about realpolitik motivations as it is about extending international trust, strategic or moralistic.

At the outset, defence diplomacy activities are foremost a show of force, particularly at the tactical level; whether these are bilateral or multilateral military exercises, coalition operations, or even purported ‘goodwill’ missions like HADR or SAR. As a baseline, such shows of force demonstrate that the state is capable, at the very least, of some form of defence. Taking this logic further, demonstrating relative superior military capabilities has a deterrent effect.Footnote ⁴⁵ Through competition in shows of force during defence diplomacy, militaries are able to demonstrate and gauge their relative capabilities, which consequently affects whether or not a state is able to deter a potential enemy. Such competition may involve achieving victory in war games during military exercises, contributing more than the others to coalition operations, or responding first to HADR missions.

The case of Singapore and its military, the Singapore Armed Forces (SAF), illustrates this juncture between deterrence and defence diplomacy clearly. The mission statement of Singapore's Ministry of Defence and the SAF highlights that the two pillars of ‘deterrence and diplomacy’ are employed ‘to enhance Singapore's peace and security’.Footnote ⁴⁶ However, in addition to the obvious use of diplomacy as a peaceful means of managing interstate relations or a way to prevent crises, as typical of defence diplomacy, there is a double entendre herein as diplomacy is also meant to smooth insecurities generated by the classic security dilemma when Singapore enhances its deterrence by boosting its military capabilities.Footnote ⁴⁷ Furthermore, deterrence and (defence) diplomacy are meant to be twinned rather than separated. As an SAF officer wrote, ‘the SAF's participation in international security and humanitarian efforts, such as peacekeeping or peace support operations, anti-piracy, HADR, etc. earn Singapore the friendship and respect of our key partners’, but they also ‘contribute to deterrence by profiling and validating our Army's capabilities and operational readiness’.Footnote ⁴⁸ Another commentator on the SAF similarly noted that ‘Singapore's presence in multilateral operations and regional HADR missions provides a “show-case” of the SAF's expeditionary capabilities in a low-profile manner’ so as to indicate ‘a visible “big-stick” whenever any of its [Singapore's] vital lifelines or national interests are threatened.’Footnote ⁴⁹

Subsequently, competition in terms of swaggering is about seeking a higher relative status. Status, or prestige, is ‘the individual or collective desire for public recognition of eminence as an end in itself’.Footnote ⁵⁰ Prestige matters because the ‘fundamental ordering principle of international politics is hierarchy, not equality’, with higher status thereby potentially giving states greater influence.Footnote ⁵¹ In defence diplomacy activities, status-seeking behaviour is associated with the demonstration of greater military strength – greater swaggering – particularly since power is arguably best illustrated by material military capabilities. This is not only reflected in performing better than other militaries in military exercises or operations, for instance, but also by doing better than their peers when military personnel are sent to participate in overseas military courses. Thus, those selected for such courses usually represent their military's crème de la crème.

An evident example of defence diplomacy used as a status device was the search for AirAsia flight QZ8501 in 2014. The plane, en route from Surabaya, Indonesia to Singapore, crashed into the Java Sea, with a total loss of lives onboard. The discovery of the wreckage of the main fuselage by Singapore was first published by Singapore's Defence Minister Ng Eng Hen on his Facebook page, rather than announced by the Indonesian SAR authority, Basarnas, even though Singapore had already updated Basarnas on the find. Moreover, Singapore had also been ‘quick to demonstrate its willingness to contribute to the search more capably than Indonesia’, deploying multiple naval and air assets for the search, including the MV Swift Rescue, the only submarine SAR ship in the region.Footnote ⁵² This swaggering resulting in a higher status also contributed to Singapore's ‘visible big stick’.

Last but not least, when we say states compete in secrecy, we mean not only that states try to outdo each other in hiding their military secrets, but also emphasise the obverse aspect in that a state wants to uncover the military secrets of others as much as it wants to prevent others from finding out such information. This is particularly relevant with regard to states that are not trustworthy and are not, therefore, part of a security community, but rather, can be potential enemies.Footnote ⁵³ Competition in secrecy can even turn into what Erik Lin-Greenberg terms a ‘non-traditional security dilemma’. This is a predicament for a state facing the choice between declining to participate in military operations other than war, such as defence diplomacy activities, thereby leading to criticism from domestic or international constituencies which believe in its ostensible benign and cooperative outcomes; or deploying but ‘potentially reveal military capabilities that rivals perceive as threatening, ratcheting up security competition’.Footnote ⁵⁴ Hence, when militaries participate in defence diplomacy activities, even as these help to build military-to-military ties, they are also concurrently doing two other things: hiding their own capabilities, as well as trying to understand the secret capabilities of other militaries, not only to learn from them to boost their own capabilities, but crucially to figure out how to counter them if necessary.

With regard to the former, hiding information about capabilities might negatively affect the effectiveness of the operation. For example, in the counterpiracy defence diplomacy activity off the coast of Somalia and the Gulf of Aden, the ‘overall operational picture is disseminated via classified military systems’ such as the North Atlantic Treaty Organisation's (NATO) Maritime Command and Control Information System or the US Combined Enterprise Regional Information Exchange System. However, of the states participating in the Shared Awareness and Deconfliction (SHADE) meetings to ‘ensure that the naval forces conducting counterpiracy operations are effectively coordinating their efforts’, these classified systems are only accessible to NATO states and other US allies, such as Japan and South Korea. Other SHADE states such as Russia, China, or India in the same area of operations therefore do not share the exact same information.Footnote ⁵⁵ The latter is the other side of the secrecy coin that ensues across defence diplomacy activities, be it military exercises, exchanges between military officers, the training of foreign personnel or appointing defence attachés to other states. For instance, during the Second World War, defence attachés provided intelligence for their home states such that ‘most of the information about Axis armed forces before December 1941 came from routine, tedious, and often unappreciated peacetime observations by Army attachés’.Footnote ⁵⁶ Such roles might have evolved today with more advanced technologies, but not fundamentally changed.

As states compete in shows of force, swaggering, and secrecy in defence diplomacy, the potential for building greater strategic trust is limited, but even more so, this competition adversely affects the building of moralistic trust as states try to outdo each other rather than develop common values to build a generalised trusting relationship. Worse, as these competition regimes become institutionalised, a vicious cycle is set off that deepens mistrust as even ostensive cooperative defence diplomacy initiatives are used for relative gains at the expense of the other. Again, this is not to suggest that defence diplomacy activities are merely excuses to ferret out military secrets, enhance influence, or amplify deterrence – if this were the case, these activities would cease to qualify as defence diplomacy as it is typically understood. Rather, our argument holds that defence diplomacy is as much about competition as it is about cooperation, about defence and not just diplomacy. It thus represents a notable paradox in that the motivations of defence diplomacy to build trust may be overturned to the extent that ‘even the most-benign military deployments can amplify mistrust and arms racing’, as Lin-Greenberg puts it.Footnote ⁵⁷

In order to assess empirically whether and if defence diplomacy affects trust between states, we operationalise trust based on two commonly used indicators. First, because trust is the belief that one can safely delegate control to others, it can be demonstrated in the voluntary acceptance of vulnerability, meaning that we should observe an opening up to others.Footnote ⁵⁸ If trust is not only strategic but moralistic or generalised, states do not perceive themselves as vulnerable given their confidence that the other will care for their interests.Footnote ⁵⁹ Conversely, as long as states are suspicious that their trust will be betrayed, or if there is only strategic trust, they will use specific safeguards to shield themselves from the risk of exploitation. Second, states may ‘under-balance’ against threats in some cases,Footnote ⁶⁰ leaving them vulnerable for reasons other than trust. It is thus necessary that to evidence trust, in addition to the voluntary acceptance of vulnerability, we observe changes in the hedging behaviour of states against the potential of betrayal by others. With increasing trust, hedging strategies such as the cultivation of alternative partners, projects and networks should become less important as states do not mind their dependence and vulnerability vis-à-vis others.Footnote ⁶¹ Our case study in the next section examines how the paradox of defence diplomacy plays out through these indicators, beginning with a brief background of defence diplomacy in Southeast Asia.

Competition in disguise: Defence diplomacy in Southeast Asia and peacekeeping operations

Although defence diplomacy activities permeate Southeast Asia's international relations today, they had a comparatively late rise in the region.Footnote ⁶² With issues of security and defence being particularly sensitive prior to the 1990s, defence diplomacy had been almost exclusively a bilateral exercise. Most of the early multilateral interactions only involved lower-ranking officials until 2006, when the ASEAN Defence Ministers’ Meeting (ADMM) was inaugurated to bring together defence officials and military officers at the highest level, with the goal to ‘promote mutual trust and confidence through greater understanding of defence and security challenges as well as enhancement of transparency and openness’.Footnote ⁶³ By 2011, one of the main contributions on defence diplomacy in Southeast Asia could state that given the ‘growing number of peacetime cooperative efforts in the region at both the bilateral and multilateral levels in the area of defence and military issues’, Southeast Asia has become a ‘useful litmus test for defence diplomacy’.Footnote ⁶⁴ These bilateral and multilateral activities include: the various military exercises conducted between regional armed forces, such as the annual Malapura exercise between Singapore and Malaysia, or the annual Bersama Lima exercise under the ambit of the Five Power Defence Arrangements between Malaysia, Singapore, Australia, New Zealand, and the UK; the Network of ASEAN Defence and Security Institutions, a track two workshop between ASEAN member states started in 2007; or the Shangri-La Dialogue, a Track 1.5 security forum organised by the International Institute of Strategic Studies and held annually in Singapore since 2002, dubbed ‘Asia's premier defence summit’.Footnote ⁶⁵ This list is naturally non-exhaustive.

On the other hand, there is a key difference between defence diplomacy in Southeast Asia and in other regions, mainly Europe. Whereas defence diplomacy's democratisation and professionalising civil-military relations role was stressed when the concept first developed in post-Cold War Europe, this particular ‘transformative’ role was lost in translation to Southeast Asia.Footnote ⁶⁶ This democratising role had naturally been sidelined there given the aversion regional states have long held towards external interference in domestic affairs, a principle that had been enshrined within ASEAN itself.Footnote ⁶⁷

Though ASEAN is commonly seen as the most successful regional organisation after the European Union in fostering relations between states, observers also note that the virtuous cycle of defence diplomacy regimes does not adequately characterise the empirical situation in Southeast Asia. In spite of the growth of bilateral and multilateral defence diplomacy activities, there is still an ‘enduring mistrust’ that has ‘undermined the establishment of a security community in the region’.Footnote ⁶⁸ Indeed, ASEAN member states still prepare for armed conflict with each other due a lack of moralistic trust, notwithstanding the self-declared ASEAN Political-Security Community (APSC) at the end of 2015.Footnote ⁶⁹ Moreover, although ASEAN is generally credited for having advanced some level of strategic trust among its members, this is seen as rather tenuous, and as former Indonesian Foreign Minister Marty Natalegawa also admits, not irreversible.Footnote ⁷⁰ ASEAN states also deny the ASEAN Secretariat independent competencies, preferring to maintain oversight of it, which is a strong indicator of a lack of trust that the collective will benefit all of its members. Defence diplomacy has therefore only been partially successful in Southeast Asia at best, as the following case study of peacekeeping further demonstrates.

Peacekeeping is generally seen as a policy area of ‘soft’ security suitable to foster relations and trust between militaries and states. Not only are peacekeeping operations typically multilateral, taking place under the auspices of an international organisation, mostly the UN, the training and preparation for peacekeeping necessarily involve a high degree of internationalisation. By definition, peacekeeping also lacks a clearly defined enemy, which turns it into a potentially fruitful activity of defence diplomacy.Footnote ⁷¹

In the regional context, peacekeeping is an area of the vibrant defence diplomacy scene. It became an issue on the Southeast Asian policy agenda in the 1990s, in line with an overall trend that saw states from the global South gradually replacing Western militaries in carrying out peacekeeping operations.Footnote ⁷² The ASEAN Regional Forum (ARF) and the ADMM-Plus, through the latter's Experts Working Group on peacekeeping in particular, promoted a range of peacekeeping-related activities with the declared goal to enhance regional peace and cooperation. The ARF stated as early as 1996 that ‘the discussion on the subject of peacekeeping in the ARF context promotes greater understanding in the Asia Pacific region’.Footnote ⁷³ Over the years, it implemented different fora for exchange and deliberation, such as a regular Peacekeeping Experts’ Meeting between 2007 and 2013. More recently, the APSC Blueprint 2025 expressed the conviction that active participation in peacekeeping by Southeast Asian states was central to create a ‘peaceful, secure and stable region’.Footnote ⁷⁴

Nevertheless, these and other similar declarations failed to specify how exactly peacekeeping was supposed to further greater understanding and regional peace while glossing over the fact that activities in and around peacekeeping were simultaneously motivated by competitive goals in deterrence, status seeking, and secrecy. As we shall show in this section, a number of initiatives to cooperate in the area of peacekeeping notwithstanding, reticence, and even mistrust prevailed.

As a baseline, it is commonly acknowledged that individual peacekeeping contributions are motivated by a range of different political, economic, security, institutional and normative concerns.Footnote ⁷⁵ ASEAN states look at peacekeeping as a ‘long-term investment into [military] professionalism’ (Indonesia),Footnote ⁷⁶ as a way to reinforce the military's ‘capacity to undertake small scale operations in difficult environments’ (Brunei),Footnote ⁷⁷ or ‘to deal with complex procedures in multinational operations alongside the most advanced militaries in the world’ (Singapore).Footnote ⁷⁸ However, on top of these operational rationales, ASEAN states also see, among the benefits of peacekeeping as a venue for international cooperation, opportunities for demonstrating and enhancing their military capabilities, deterrence, and swaggering.

In terms of shows of force, when Singaporean peacekeepers deployed to East Timor in September 1999, then Senior Minister Lee Kuan Yew, also Singapore's founding prime minister, clearly enunciated the deterrent rationale behind the deployment as: ‘If we don't go, our neighbours will think we are “scaredies” and therefore, that we can be trampled on.’Footnote ⁷⁹ The same idea was expressed a decade later when Singapore sent peacekeepers to Afghanistan in order to demonstrate it was a ‘player’ shaping international security; otherwise, ‘what will happen is that we will just be a bystander and that environment around us will be shaped and determined by other people’, as Singapore's then Defence Minister Teo Chee Hean emphasised.Footnote ⁸⁰ Hence, even as peacekeeping served the SAF's operational needs such as training space or actual missions, the traditional military function of power projection and deterrence was a major consideration for Singapore, too. Likewise, as the head of the Thai military's peacekeeping training centre explained, Thailand sees the UN as a cornerstone of its security and hence ‘its contributions of military service to UNPKO [UN peacekeeping operations] as an intrinsic agenda of its military strategy in deterring threats to the kingdom’.Footnote ⁸¹

In some cases, notably those of Indonesia and Malaysia, an active peacekeeping profile has served to swagger when peacekeepers were sent abroad to bolster their ‘middle power status’ and ‘promote themselves within the international system’.Footnote ⁸² Indonesia has been Southeast Asia's most visible peacekeeping contributor since 2012, when it declared its goal to become one of the top ten contributors to UN peacekeeping.Footnote ⁸³ This ambition was invariably linked to its quest for regional and global ‘actorness’. Thus, Indonesia ‘prided itself’ in being an active peacekeeping contributor not because its main objective has been to insert its military into a multilateral setting.Footnote ⁸⁴ Rather, in a mix of status-seeking and deterrence, it has sought to demonstrate its military capacity and determination to defend Indonesian interests. For example, since 2009, Indonesia has been part of the UN Interim Force in Lebanon's Maritime Task Force, an engagement that has fitted neatly with the country's recent-found emphasis on maritime affairs. In addition, since peacekeeping has been a policy area tied to the politics of Indonesia's middle power identity, the country has had fewer incentives to engage in cooperation initiatives with other ASEAN states as these would dilute its position as a regional leader.Footnote ⁸⁵

Motivations such as opportunities for deterrence and swaggering are surely legitimate and not unique to Southeast Asia. Similarly, though we could not find examples of ASEAN states competing with regard to secrecy in the public domain, especially since ASEAN states are very sensitive to such matters, there cannot be doubt that such exists. For instance, some US observers ‘have suspected that’ Chinese ‘“peacekeepers” collected intelligence on foreign militaries and focused on protecting China's economic, including energy, investments, or facilities’.Footnote ⁸⁶ Once competition in shows of force, swaggering, and secrecy are taken seriously, it appears far less obvious why intra-ASEAN information sharing, training exchanges and other cooperation initiatives centred on peacekeeping, as well as ASEAN's declared goal to develop a ‘regional identity in peacekeeping operations’ that could serve as the basis for moralistic trust,Footnote ⁸⁷ would actually further trust between ASEAN states and their militaries in practice.

Furthermore, the aforementioned statements about the ostensive positive outcomes of peacekeeping within the context of regional cooperation notwithstanding, few substantive initiatives have actually been implemented.Footnote ⁸⁸ In other words, the ASEAN states have neither opened up nor granted each other room to leverage policy decisions that could render themselves vulnerable, strongly indicating a lack of trust among them. Although ASEAN has officially cited differences in capacity and military doctrines as an obstacle to integrate the region's peacekeeping policies, such practical problems could be overcome if there was political will backed by trust that cooperation would further mutual, instead of individual, interests. The only area that has seen substantial progress was student and instructor exchanges, though these have been managed on a bilateral basis. Importantly, these have often been required by peacekeeping donor countries supporting local peacekeeping training centres, such as the US under its Global Peace Operations Initiative. They should therefore not be seen as ASEAN states voluntarily opening up to each other. The lack of regional emphasis on such multilateral initiatives could thus also be interpreted as a preference for maintaining secrecy over their military establishments rather than opening the door to other ASEAN states and reaping the benefits of cooperation. Furthermore, within the ASEAN Peacekeeping Centres Network, which had begun to function as a Peacekeeping Centre Association in 2009, joint actions have been decided at the bilateral level and not multilaterally, pointing to the fact that the ASEAN states have preferred to maintain multiple, cost-effective channels as a hedge. Hence, a decade after its conception, the Network has remained far from attaining the objectives established in its concept paper, namely to enhance interoperability between the ASEAN members and develop ‘a common standby arrangement to support peacekeeping operations’.Footnote ⁸⁹

Unlike other states in Africa and Europe, the members of ASEAN have not followed the UN's call upon regional organisations to step up their engagement and share the burden of peacekeeping operations by creating standby forces or other capacities.Footnote ⁹⁰ While the idea to create an integrated Southeast Asian peacekeeping force has sporadically been voiced as early as the 1980s, it has never been thoroughly discussed.Footnote ⁹¹ Due to prevailing suspicions between states, most have been unwilling to incur the risk of putting some of their national assets at the disposition of the collective. Indonesia, the then ASEAN chair, formally put forth the idea to develop a regional peacekeeping capacity in 2003 as part of the APSC it was promoting at that time.Footnote ⁹² Previous ASEAN declarations about the potential positive impact of broader cooperation in peacekeeping to the contrary, this Indonesian proposal was quickly put off the table. Singapore considered ASEAN to be the wrong venue, Vietnam thought it was too early, and Thailand opined ‘that it was unnecessary to form an ASEAN Peacekeeping Force because “there is no conflict in the region which would need the mobilisation of such a force”’.Footnote ⁹³ The Thai statement not only neglected a long-standing conflict in its southernmost region, but also an armed rebellion of Muslim separatists in Mindanao in the southern Philippines, Timor Leste's bloody path to independence, and a rebel movement in Aceh, all of which saw peacekeepers from Southeast Asia and other states during the early 2000s. Thailand's repudiation was thus an expression of unease with relinquishing secrecy in an integrated peacekeeping force, together with the risk of strong pressures to use such a force to address the region's conflicts once it was created. The main reasons for the dismissal for Indonesia's peacekeeping proposal were thus ‘political and strategic in nature rather than financial or military concerns’. An Indonesian foreign affairs official hinted that the lack of trust was the true reason behind the opposition to Indonesia's peacekeeping proposal in emphasising that ‘we only changed the wording because some countries are still sensitive to the words’, but the ‘idea’ of peacekeeping was maintained in the APSC.Footnote ⁹⁴ Such sensitivity was symptomatic of perceptions that trust within ASEAN would be betrayed.

The prevailing competitive thinking and mistrust towards fellow ASEAN members did not change in the following years despite ASEAN's active defence diplomacy agenda, including in the area of peacekeeping.Footnote ⁹⁵ There was neither greater acceptance of vulnerability through advances on the regional peacekeeping agenda, nor a reduction in Southeast Asian hedging strategies, such as a concentration of cooperation initiatives on ASEAN away from extra-regional partners, for instance. In celebrating the 70^th anniversary of Thai-Indonesian diplomatic ties in 2020, which included mention of Thailand dispatching ‘troops for peacekeeping operations in East Timor in 1999’, Thailand's ambassador to Indonesia highlighted that ‘when uncertainties spread across the world, we cannot take for granted our cordial and nonviolent relations’, even as he pushed for stronger relations between the two ASEAN states.Footnote ⁹⁶ Indeed, less than a decade after the idea of a regional peacekeeping arrangement was put on the table, Indonesian military observers stood ready to deploy along the Thai-Cambodian border in 2011, where a deadly stand-off had prompted the UN Security Council to call for the region to act.Footnote ⁹⁷ Out of a position of pride, if not arrogance, the Thai army refused to consent to the operation with a number of high-ranking officers pointing out that ‘we are not Africa’, suggesting that Thailand could take care of its problems on its own while at the same time maintaining secrecy.Footnote ⁹⁸

In any case, Indonesia's foreign policy elite had few illusions as to the success of its proposal.Footnote ⁹⁹ The idea to create a regional peacekeeping force provided the country with an opportunity to swagger in that it positioned Indonesia as a norm entrepreneur and regional leader in security matters.Footnote ¹⁰⁰ If a regional peacekeeping force would be created in the future, Indonesia would be on record as the first to propose the idea. The lack of political influence behind the proposal also likely explained why the idea of creating an integrated peacekeeping force has largely stagnated. An exception was a statement in favour of an ASEAN peacekeeping force made by then Malaysian Defence Minister Hishammuddin Hussein in 2015, which was largely ignored by the other ASEAN states.Footnote ¹⁰¹ During this time, Malaysia had strong incentives to portray itself as an active player internationally as it held both the ASEAN chairmanship role and a non-permanent seat at the UN Security Council. Furthermore, Malaysia's proposal should be interpreted as a response to Indonesia's pro-cooperation stance, as the two countries have developed ‘a level of healthy competition’ over regional leadership in peacekeeping.Footnote ¹⁰² Just as neither wanted to remain behind when peacekeeping was put onto the agenda of ASEAN, both also sought to position their peacekeeping centres as a regional ‘hub’ and centre of excellence.Footnote ¹⁰³ It is difficult to see how such rivalry can further strategic trust between the two states, nor to speak of any level of confidence that one will care for the other's interests if presented with an opportunity to further its own advantage.

Importantly, mistrust between states has not only persisted, it has arguably deepened in relation with the proposals to enhance cooperation in matters of peacekeeping as they have been interpreted by some simply as a pretext to intervene in the internal affairs of other ASEAN members. Thus, it has often been noted that ASEAN states disagree over what constituted a legitimate framework for peacekeeping operations.Footnote ¹⁰⁴ The participation of Singapore and Malaysia in so-called ‘peacekeeping’ efforts outside the framework of the UN, such as in Iraq, Afghanistan, and the Gulf of Aden, have raised eyebrows in the other ASEAN states. Although these operations have been justified with reference to UN resolutions, they have sparked serious concerns as expressed to us in informal conversations with ASEAN officials from member states reluctant to support deployments not directly sanctioned by the UN Security Council, especially if these tend towards a more robust use of force. Since the creation of a regional peacekeeping force would not be justifiable if it were for extra-regional use only, various states have refused to move ahead with the idea in order to avoid greater vulnerability through what they suspect would turn into an interventionist regional policy agenda.Footnote ¹⁰⁵ This logic was evidently at play in Myanmar's Muslim Rohingya crisis. Forgoing the opportunity to demonstrate that it was a credible and capable actor at the international scene, ASEAN's response, to what UN Secretary-General António Guterres called ethnic cleansing in Myanmar's Rakhine state, was undecisive and failed to answer calls for regional peacekeepers, especially from majority-Muslim Indonesia and Malaysia.Footnote ¹⁰⁶ Even discussing the crisis was ‘outside of the bloc's comfort zone’, given that it would likely further deepen mistrust and drive a rift between ASEAN's members.Footnote ¹⁰⁷

Although an ASEAN peacekeeping force in which states relinquish control to a joint command may be considered a too radical transformation for defence diplomacy to achieve, ad hoc cooperative arrangements for individual deployments as practised in other regions have also been rare. Overall, ASEAN states have preferred to do peacekeeping on their own in order to take credit for the ostensive image-polishing activity. Internationally integrated units have helped to offset costs if a state lacked qualified personnel or necessary equipment to deploy, but they have fallen short of offering the same opportunities of swaggering. Hence, only two Southeast Asian states have integrated personnel with other Southeast Asian militaries. Singapore, building on previous experiences with embedding personnel with more experienced or larger professional armies from the West,Footnote ¹⁰⁸ sent an infantry company as part of a Thai battalion to the UN mission in East Timor. Rather than a strategy to build trust, however, this one-off situation likely simply reflected Singapore's military deployment strategy as a small state. The second case, Brunei, was the exception that confirmed the rule. Brunei embedded peacekeepers several times, with Malaysia (in Mindanao and UNIFIL, Lebanon) and with Indonesia (Mindanao), explained by the fact that Brunei's seven-thousand-personnel-strong military is plainly too small to rival its Southeast Asian counterparts. Hence, in this successful case, the absence of competition was tellingly a precondition rather than a result of cooperation.

In summary, even as peacekeeping as an exercise in cooperative defence diplomacy has taken off in Southeast Asia, ASEAN states have also deemed peacekeeping to be an opportunity for competitive deterrence, swaggering, and secrecy. We acknowledge that we have not presented any ‘smoking gun’ evidencing such competition and increased mistrust. This is especially challenging since defence diplomacy is about ‘diplomacy’ on the surface, and also owing to the fact that ASEAN states are extremely sensitive about such matters. Nonetheless, our case study has shown how peacekeeping as an instrument of defence diplomacy has been motivated and practised based on realpolitik considerations by the ASEAN states. Furthermore, our case study has also demonstrated that ASEAN states have neither opened up to each other, nor reduced their hedging to mitigate their vulnerabilities. Instead, mistrust has continued to prevail and substantive cooperative peacekeeping measures, such as a regional peacekeeping force, have remained elusive despite the rise in the exercise of defence diplomacy in Southeast Asia. Future research may probe this argument further with specific reference to the state of strategic or moralistic trust itself, between Southeast Asian states.