The signing of the Jakarta Treaty of 2026, or the Indonesia-Australia Treaty on Common Security in February 2026 marked a new chapter in bilateral relations between Indonesia and Australia. This treaty is not merely a formal written document. It reflects the maturity of Indonesia’s defense diplomacy, demonstrating growing confidence in forging strategic partnerships without compromising the fundamental principles of its foreign policy.
Indonesia's defense and foreign policy under the leadership of President Prabowo Subianto (2024–2029) is grounded in the free and active and non-aligned principles, combined with a focus on strengthening national self-reliance and prioritizing a good neighbor policy.
Indonesian Foreign Minister Sugiono is scheduled to attend the 10th Indonesia-Australia Foreign and Defence Ministers' Meeting, known as the "2+2" meeting in Melbourne, Australia, on August 26, 2026. This forum represents a significant agenda for discussing the strengthening of bilateral relations between Indonesia and Australia, including defense and security, which are matters of shared concern.
During the meeting, the two countries are scheduled to discuss a number of issues, including the implementation of the Treaty on Common Security, defense and security cooperation, conflict prevention, and maritime security.
Discussions will also cover economic resilience and supply chains, in addition to various other issues of mutual interest to Indonesia and Australia. This paper aims to describe Indonesia's defense diplomacy through defense cooperation with Australia, following the signing of the Jakarta Treaty in 2026.
The Jakarta Treaty represents the culmination of a long history of defense cooperation between the two nations, dating back to 1995 when President Suharto and Prime Minister Paul Keating signed the first security agreement.
This treaty builds upon the 2006 Lombok Treaty but offers broader and deeper scope. Australian Prime Minister Anthony Albanese has emphasized that no country is more important to Australia, or to the prosperity and stability of the Indo-Pacific, than Indonesia.
However, what distinguishes the Jakarta Treaty from previous agreements is the concept of common security it embodies. Unlike conventional military alliances such as AUKUS (Australia, the United Kingdom, and the United States), this treaty does not mandate automatic mutual defense should one party face a threat.
Therefore, as Australian Assistant Minister Matt Thistlethwaite has affirmed, the treaty serves instead as a mechanism for consultation and coordination on shared security issues, while respecting the sovereignty and legal frameworks of both nations.
Indonesian Foreign Minister Sugiono has also previously emphasized that the treaty functions as a platform for security consultations at the leadership and ministerial levels. ‘This is not a mutual defense pact; there is no such obligation,’ he asserted.
This distinction is crucial given the differing threat perceptions held by the two countries, in which Australia views China as a strategic competitor, whereas Indonesia does not regard China as a direct security threat. Substantially, the treaty's design which entails no binding military obligations makes it an ideal instrument for Indonesia to maintain its independent and active foreign policy stance.
Expanded Scope of Inter-State Defense Cooperation
The Jakarta Treaty expands the scope of defense cooperation beyond traditional sectors. The collaboration encompasses areas ranging from defense and maritime security to cybersecurity and economic resilience. This expansion reflects the understanding that security in the contemporary era is no longer monolithic but multidimensional.
Implementation of the treaty is being realized through various concrete initiatives. One of the most significant breakthroughs is the posting of an Indonesian National Armed Forces (TNI) officer with the rank of colonel as the deputy commander of the Australian Defence Force’s 1st Brigade in Darwin, starting next year.
The officer will remain under TNI command while being institutionally integrated into the Australian defense structure, working alongside the rotational US Marines stationed in Darwin. This move represents a pinnacle achievement in institutional relations between the two defense forces.
Australia has also committed to supporting the development of defense training facilities in Indonesia, particularly on Morotai Island, North Maluku. A military survey team will be deployed to assess the potential for infrastructure development at the site, which retains remnants of World War II-era infrastructure.
Australian Defence Minister Richard Marles described this initiative as Indonesia-led while noting that it also presents a major opportunity for Australia to conduct joint military training in the future.
Inclusive Defense Diplomacy
Indonesia’s defense diplomacy under the Jakarta Treaty also emphasizes human resource development and the building of long-term networks. The Young Leaders Forum, scheduled for October 2026, will see its duration extended and for the first time include a component held in Indonesia. This program offers junior officers specifically captains and lieutenants the opportunity to establish professional relationships with their counterparts in both countries.
Also, Matt Thistlethwaite emphasized the importance of focusing on young personnel so they can build networks early in their careers, thereby maintaining open lines of communication when facing future challenges. The Australian government is also providing additional funding to the Australia-Indonesia Institute to enhance Indonesian language proficiency and understanding of Indonesia within Australia.
The Jakarta Treaty is not only mutually beneficial for both nations but also holds the potential to strengthen broader regional stability. Australia has expressed confidence that this cooperation can be expanded to the wider ASEAN sphere, given Australia's current status as an ASEAN Plus dialogue partner.
For Australia, national security is inextricably linked to the collective security of Southeast Asia, a region where Indonesia lies at the heart. For Indonesia, the treaty reflects a steadfast commitment to the principles of good neighborliness and a tangible contribution to peace and stability across the Indo-Pacific region.
The 2026 Jakarta Treaty represents a significant achievement in Indonesia's defense diplomacy, demonstrating maturity in forging strategic partnerships without compromising sovereignty or the principles of its free and active foreign policy.
Designed as a security consultation agreement rather than a military alliance, the treaty allows Indonesia to remain flexible in responding to regional dynamics while deepening ties with Australia to an unprecedented level.
Bilateral cooperation, encompassing officer exchanges, the development of training facilities, and programs to cultivate future military leaders demonstrates that Indonesia's defense diplomacy is becoming increasingly focused and sustainable, making a tangible contribution to peace and stability in the Indo-Pacific region.
