Indonesia’s Partnership Building: Free, Active and Untested.
Strategic Question
Can Indonesia Maintain Strategic Autonomy as its Security Partnerships Expand?
Key Judgement
Indonesia continues to manage its “free and active” foreign policy by engaging regionally in bilateral and potentially trilateral agreements.
Indonesia has accelerated its regional partnerships, but these remain largely untested. The operationalisation of these partnerships may place additional pressure on its “free and active” policy, particularly if security integration deepens and joint military exercises expand.
Core Assessment
On 26 August, defence ministers from Australia, Japan, and Indonesia met virtually to discuss the Indo-Pacific security environment, economy, and development. The countries reaffirmed their commitment to contributing to the region's peace and stability, with the meeting following the Australia-Indonesia Treaty on Common Security (the Jakarta Treaty). At the first meeting between the three countries, ministers agreed to deepen trilateral defence cooperation. While still at an initial stage, the talks broaden Indonesia’s engagement in the region, alongside strengthening bilateral defence ties with Australia, Japan, and China.
Background
Indonesia’s foreign policy towards the region is shaped by its long-standing ‘bebas aktif’ (free and active) commitment to international engagement. Australia has maintained defence cooperation with Indonesia, strengthened through the 2024 Defence Cooperation Agreement and the recent signing of the 2026 Treaty on Common Security (Jakarta Treaty). In June 2026, Japanese and Indonesian defence ministers met to reinforce bilateral defence cooperation under the Defence Cooperation Arrangement (DCA). More recently, on 20 August, China and Indonesia agreed to strengthen military and economic ties, including cooperation on minerals, technology and energy. The 20 August meeting followed a joint military exercise between China and Indonesia held east of Taiwan.
Strategic Assessment
Indonesia’s geography, economic scale and regional influence make it a strategically important partner. Despite Indonesia’s unwillingness to align exclusively in the region, maintaining relations with Jakarta remains important for competing powers. Sitting between the Indian and Pacific Oceans and alongside the Strait of Malacca, Indonesia’s archipelago also provides alternative maritime routes through the Sunda and Lombok Straits, with the deeper Lombok Strait providing an alternative to the shallower waters in the Strait of Malacca. The two straits are increasingly important for avoiding congestion in the Strait of Malacca, while the deeper Lombok Strait provides an alternative for deep-draft vessels carrying energy. With a population of more than 280 million, Indonesia is Southeast Asia’s largest economy.
Indonesia has managed to maintain and build non-exclusive defence relationships, with some expanding more recently. The agreement to strengthen military and economic ties between China and Indonesia, alongside the joint military exercise, preceded the latest trilateral defence ministers' meeting with Australia and Japan by a week. Indonesia is presenting these relationships as compatible rather than as indications of alignment, and the country’s strategic importance incentivises partners to build relationships rather than demand exclusive alignment. For regional partners, applying alignment pressure risks reducing influence and allowing competing partnerships to strengthen.
Indonesia has engaged in building regional partnerships; however, many remain underdeveloped and largely untested. The Jakarta Treaty signed in February 2026 aimed to deepen defence cooperation and consultation on security challenges, and the two countries are working towards operationalising it. Other recent Indonesian security developments include the 2024 Australian DCA, the May 2026 Japan-Indonesia DCA, a commitment to boost security and economic ties with China on 20 August 2026, and the trilateral meeting with Japan and Australia on 26 August 2026. Despite the acceleration in Indonesia’s partnership building, the relationships are yet to be fully operationalised, allowing them to coexist. As some contain intentions to share intelligence and sensitive technology, develop contingency planning and build interoperability, political pressure may increase due to the sensitivities that accompany deeper security cooperation.
What to Watch
Operationalisation of the Jakarta Treaty and bilateral DCAs, particularly intelligence sharing, transfers of defence technology, and interoperability.
Progress in the Australia-Japan-Indonesia trilateral cooperation and indications of planned exercises, consultations or deeper defence cooperation.
Indonesia-China military, defence-industrial and economic cooperation.
Diplomatic statements that create political pressure on Indonesia’s regional relationships.
Strategic Indicators
Indonesia's Strategic Importance ▲ Increasing
Indo-Pacific Bilateral/Minilateral Security Cooperation ▲ Increasing
Indonesia continues to manage its “free and active” foreign policy by building bilateral and potentially trilateral agreements. A combination of geography, economic scale and willingness to engage has created strategic leverage for Jakarta as a regional partner. While Indonesia has accelerated its regional security partnerships, these remain largely untested in terms of how they will be operationalised and how regional partners will respond if security ties deepen. The operationalisation of newer agreements and responses from regional partners may create additional pressure on Jakarta, particularly if security integration deepens.
Sources
Government and Defence Sources
Japan Ministry of Defense — Australia-Japan-Indonesia Trilateral Defense Ministers’ Meeting
Japan Ministry of Defense source
Australian Department of Foreign Affairs and Trade — Australia-Indonesia Treaty on Common Security
Australian DFAT source
Japan Ministry of Defense — Japan-Indonesia Defense Ministerial Meeting
Japan Ministry of Defense source
Australian Department of Defence — Australia-Indonesia Foreign and Defence Ministers' Meeting
Australian Defence source
Economic and Maritime Sources
World Bank — Indonesia: Overview and Economic Data
World Bank source
Defence Connect — The Indo-Pacific's Maritime Choke Points: Sunda and Lombok
Defence Connect article
Eurasia Review — Beyond Malacca: Securing ASEAN's Strategic Waterways
Eurasia Review article
News Reporting
Reuters — China, Indonesia Ministers Meet to Discuss Security and Economic Ties
Reuters article
Reuters — Indonesia, Japan Sign Defence Cooperation Agreement
Reuters article
Asia News Network — Between OECD and BRICS: Indonesia's Bebas Aktif Conundrum
Asia News Network article