SYNOPSIS

In examining the contemporary development of Japan-ASEAN security cooperation, the Official Security Assistance scheme, newly introduced by the Government of Japan, is an important subject of analysis. This article outlines the institutional characteristics of this scheme and examines the significance of cooperation on issues of common regional concern to ASEAN with respect to the promotion of regional peace, stability, and confidence-building.

COMMENTARY

Japan’s Official Security Assistance (OSA) scheme was established in April 2023 as a new framework for grant aid, under which military organisations and related entities are designated as beneficiaries through the provision of equipment and materials, infrastructure development, and other forms of assistance in response to the deterrence and security needs of like-minded countries, with the objective of creating a security environment favourable to Japan.

Whereas the conventional Official Development Assistance (ODA) has primarily pursued socio-economic development, OSA is characterised by its direct focus on capacity-building in the security domain as its object of assistance.

In considering the significance of OSA for ASEAN, attention should not be directed merely towards the expansion of recipients and the scope of assistance; rather, an equally important question concerns the political implications of recipient countries’ acceptance of such assistance.

In particular, at a time when concerns are emerging that newly developing security initiatives may sideline ASEAN centrality, it is important that the institutional design of OSA has been constructed in a manner that does not contradict ASEAN centrality.

In security matters, ASEAN member states generally adopt a pragmatic position focused on the stable and steady acquisition of necessary capabilities. At the same time, some countries are cautious about excessive dependence on particular major powers amid the sharpening of great-power rivalry. Accordingly, due consideration for ASEAN centrality and the strategic autonomy of individual AMSs is also essential.

Therefore, Japanese assistance, which presupposes the maintenance of the autonomy of individual states, is limited to areas not directly connected to international conflicts. While aiming at capacity-building, through the provision of equipment, training support, and improvements in information-sharing, it is consistent with ASEAN needs and may consequently be regarded as one of the more readily acceptable forms of cooperation.

Practices in Southeast Asia

In the regional maritime areas, including the South China Sea, containing tensions and avoiding accidental clashes remain important amid rising maritime activity and the intensification of grey-zone situations by various states. In particular, AMSs, many of which encompass multiple major sea lines of communication, are seeking to enhance their autonomous security capabilities. Furthermore, owing to the frequent occurrence of natural disasters arising from geographical conditions, strengthening disaster response capabilities has also become an urgent challenge.

Against the backdrop of these accumulating regional challenges, the areas covered by OSA are closely linked to fields that ASEAN has identified as matters of common concern, including Maritime Domain Awareness (MDA), Humanitarian Assistance and Disaster Relief (HA/DR), and international peace cooperation activities.

For example, Japan has supported the enhancement of the Philippines’ coastal surveillance capabilities primarily by providing coastal radar systems and related equipment. In the South China Sea, where disparities in capabilities among claimant states have become increasingly pronounced, such assistance may be regarded as serving not only to mitigate the risks of misperception and contingencies but also to enhance the effectiveness of deterrence.

Similarly, in Indonesia and Malaysia, both of which possess vast maritime domains and multiple sea lines of communication of critical importance to Japan and the region as a whole, Japan has supported the strengthening of MDA capabilities by providing high-speed patrol vessels, surveillance and monitoring equipment, and diving support vessels.

Such assistance facilitates timely and appropriate understanding of vessel movements based on MDA while simultaneously enhancing capacities for early responses to abnormal weather events that have frequently occurred in Southeast Asia in recent years. Improvements in these capabilities contribute to the safety and security of maritime transportation, maritime law enforcement, and disaster response, and are likely to constitute an important foundation supporting the capacity of both countries to maintain maritime order autonomously.

The fact that the development of OSA has been particularly pronounced in the maritime domain may also be understood as indicating Japan’s strategic prioritisation of Southeast Asia as a region of maritime security significance and of vital maritime chokepoints.

Correlations with Regional Frameworks

Japan has long engaged with ASEAN-led regional multilateral frameworks, including the Shangri-La Dialogue and the ASEAN Defence Ministers’ Meeting-Plus (ADMM-Plus), not merely as venues for policy articulation but as open spaces for dialogue aimed at confidence-building in the region.

Statements by successive Japanese prime ministers and defence ministers have consistently been anchored in fundamental principles, such as international law, freedom of navigation, as well as cooperation and confidence-building in crisis management, without unduly fueling great-power rivalry. The accumulation of such regional dialogue and cooperation is also likely to enhance mutual understanding and transparency within the region.

Although OSA is fundamentally implemented bilaterally between individual countries, its parallel implementation alongside existing regional frameworks suggests it may play a certain role in promoting regional peace, stability, and confidence-building. What is important here is its potential to operate in a mutually complementary manner.

Since maritime security, HA/DR, and international peace cooperation activities – fields that constitute common regional concerns – also overlap with the areas covered by OSA, strengthening individual states’ response capabilities through bilateral cooperation may, in aggregate, be understood as contributing to the preservation of ASEAN’s overall autonomy.

Moreover, OSA should be understood not as a substitute for the United States’ regional engagement but as a complementary mechanism that reinforces regional resilience even during periods of strategic uncertainty. Since the second Trump administration, the United States’ tendency to prioritise transactional relationships over alliances and institutions has become even more pronounced.

Yet, even under such circumstances, Japan has quietly supported a regional order that does not overly rely on any particular major power through ASEAN-led multilateral frameworks. While preserving the possibility of renewed US regional engagement, Japan may therefore be assessed as deploying OSA with the enhancement of ASEAN’s overall capabilities as its principal axis.

Future Outlooks and Challenges

As the regional order becomes increasingly unsettled amid intensifying great-power competition, Japan-ASEAN security cooperation may potentially be positioned as a third model distinct from both the US-style approach centred on containment and alliance strengthening directed against particular states, and China-led conceptions of regional order. This may be understood as a regional buffer mechanism that absorbs the shocks generated by great-power competition while continuing to respect and support ASEAN’s autonomy.

The greatest future challenge for Japan-ASEAN security cooperation will likely be whether this framework can be strengthened as a form of practical cooperation while remaining a “quiet strategy.” Within ASEAN, which comprises states with diverse political systems and external orientations, a matter of concern for some member states lies in maintaining a balance that avoids excessive alignment with any particular country, while also preventing the region from becoming an arena of great-power competition. External assistance that foregrounds opposition to a particular state is therefore politically difficult to accept.

In light of these circumstances, external security cooperation directed towards ASEAN must be designed as practical assistance tailored to the circumstances and needs of individual member states. In this respect, the strength of Japan-ASEAN cooperation may be understood as lying in its modest and restrained approach, which steadily supports regional stability without inflaming interstate confrontation.

This approach is underpinned by trust cultivated through decades of economic cooperation and by Japan’s consistent support for ASEAN autonomy, while considering the circumstances of individual member states.

At the Twelfth ADMM-Plus, held in Malaysia last year, Japan’s Minister of Defence, Mr KOIZUMI Shinjiro, made it clear that ASEAN-led frameworks remain a foundation for regional stability, even amid rising regional tensions, and affirmed Japan’s continued support for ASEAN centrality.

Furthermore, Japan reiterated its position that the objective of security cooperation is not confrontation but stabilisation, and characterised cooperation on issues of common regional concern as intended not for military responses directed against any particular state but rather for the prevention of accidental clashes before they occur. This may be interpreted as a political message intended to alleviate ASEAN member states’ concerns regarding inadvertent entrapment.

Conclusion

In conclusion, OSA may be viewed as a flexible framework of cooperation that, while taking into account ASEAN’s political diversity and autonomy, contributes to regional stability without exacerbating geopolitical tensions by providing bilateral assistance tailored to the needs of individual member states.

Furthermore, if Japan is to continue employing OSA as an important instrument for the sustained deepening of security cooperation with ASEAN, it will be necessary to continue steadily accumulating practical cooperation in areas of common concern while preserving both the trust cultivated over the past and the future balance of the regional order.

About the Author

SHIGETOMI Haruki is a Visiting Fellow with the S. Rajaratnam School of International Studies (RSIS), Nanyang Technological University (NTU), Singapore. He is a government official from the Ministry of Defense, Japan (JMOD). The views expressed in this commentary do not officially represent those of the JMOD nor the Government of Japan.