In light of the challenges described above, the future of trilateral cooperation remains uncertain. But three potential pathways can be identified.
First, one (or more) of the three leaders could actively damage trilateral cooperation by disparaging the cooperative framework. This path seems the least likely. Despite his broader grievances against multilateralism and minilateralism, President Trump has allowed minilateral formations in the Indo-Pacific to continue to function. At a meeting in February 2025, Trump and Ishiba reaffirmed the ‘importance of Japan-U.S.-RoK trilateral cooperation’. There is also a bipartisan consensus in the US Congress in favour of trilateral cooperation on the Indo-Pacific, as evidenced by the introduction of a bill for enhancing inter-parliamentary cooperation between the three countries.
Elsewhere, some observers fear that, despite their recent rhetoric, President Lee and Prime Minister Takaichi could inflame tensions between their countries over unresolved historic issues. However, as mentioned above, both leaders have pledged to maintain economic and security cooperation, and reaffirmed their support for the trilateral since taking office. Successful visits to Japan and the US by Lee would also seem to confirm the pragmatic turn in his foreign policy, in particular. Accordingly, the chances of any of them seeking to damage or abandon the partnership are low.
The second, most optimistic pathway – in which the trilateral partnership continues with the same level of intensity as in previous years – also seems unlikely. The level of commitment displayed by the three former leaders no longer exists at the top level. Biden pushed for a trilateral leader-level summit in almost every bilateral meeting with the heads of Japan and South Korea. Yoon was deeply convinced of the need to improve South Korea’s ties with Japan for a variety of reasons, both personal (such as the influence of his father) and strategic (particularly, the more threatening external security environment). Although their successors have acknowledged the strategic imperative, they have not yet shown a willingness to invest the same amount of personal capital.
One of the legacies of the 2023 Camp David summit is the recognition of the importance of trilateral cooperation among officials of all three countries.
Strong leadership is essential for setting a strategic vision and imbuing historically tense and complicated relationships with a positive spirit. Some of the actions taken by the three former leaders may have been purely symbolic. But symbolism is persuasive and, therefore, its value remains high. Without it, momentum will be difficult to sustain.
The third – and most likely – trajectory is that working groups and convening below the leadership level continue to function, and help to strengthen trilateral cooperation despite inertia from the top. One of the legacies of the 2023 Camp David summit is the recognition of the importance of trilateral cooperation among officials of all three countries, and the formation of mechanisms that can turn warm words and sentiment into practical action. Among the most significant of these mechanisms are the Indo-Pacific Dialogue, the coordination mechanism for the secretariat and the DTT. As such, cooperation can persist at lower levels of government to build on previous agreements – maybe even without defining any new outcomes.
Before Camp David, progress towards institutionalization was slow and trilateral meetings were infrequent. The process started in the 1990s with a coordination mechanism to co-manage common security threats from North Korea. But only in 2008 did this channel evolve into an assistant-secretary-level mechanism as the DTT, which continues to date. The first trilateral meeting of foreign ministers took place in 2010, prompted by a desire for closer economic cooperation, as well as increased North Korean provocations and political changes in Japan. Eventually, the heads of state of the three countries held summit meetings in 2014 and 2016, as the US tried to mediate ties between Japan under Shinzo Abe and South Korea under Park Gyun-hye under President Barack Obama’s ‘Pivot to Asia’ strategy.
The salience of the external security environment as a coalescing factor became ever more apparent in the following years. Even though North Korea remained the primary focus, trilateral cooperation was increasingly framed in the context of other regional and global issues. The vice foreign ministers of the three countries began to hold regular meetings, discussing issues ranging from the South China Sea to climate change and cyber threats. This wider discussion then allowed for lower-level diplomatic and military exchanges.
Camp David brought all these channels under a common framework, while also introducing new ones. Frequent meetings helped familiarize the three bureaucracies with one another, foster habits of cooperation and deepen mutual trust. Individual officials also became more familiar with the leaders’ vision for the partnership. This shared endeavour created a sense of prioritization and fostered a desire for more connections across the three governments – strengthening what an interviewee for this paper referred to as the ‘connective tissue’ of partnership. These connections also have the effect of increasing the cost of backtracking by any single country.
Talks on a formal political and diplomatic secretariat to serve as the coordination centre for the trilateral partnership began under President Biden, first becoming public in May 2024. These talks appear to have continued under President Trump, having stalled in the run up to the 2024 US presidential elections. During the talks, the South Korean government had expressed a desire to host a permanent secretariat, which idea was resisted by the Japanese government. This disagreement led ultimately to the proposal of either a virtual secretariat or one rotating between the two capitals. A secretariat with rotational heads opened in November 2024, but its mandate and role remain unclear to date.
