Tides of Trust: Rimpac’s Unlikely Harmony Raises Questions About Seoul and Tokyo’s Future

The just-concluded Rim of the Pacific (Rimpac) exercises have shown that even nations with a history of animosity can find common ground on defense. This year, South Korea and Japan took command roles alongside other participating nations, marking a significant step towards cooperation between two countries whose relationship has long been marred by disputes over their shared past.

The Rimpac drills bring together 30 nations and over 30,000 personnel for the largest maritime exercise in the world. Historically, they have provided a platform for allies to train and operate together. However, this year’s event saw unprecedented integration between South Korean Rear Admiral In-ho Kim and Japanese Rear Admiral Takuo Kobayashi at the helm of key command roles. Their seamless collaboration has sparked questions about what this means for their bilateral relations.

The fact that Seoul and Tokyo were able to put aside their differences is a testament to the power of joint military operations in building trust between nations. The US-led exercises have long served as a means of strengthening alliances and fostering cooperation among participating countries. This year, however, was notable not just because of their presence but also because of their ability to work together effectively.

US Vice Admiral Jeffrey Jablon’s remarks on the “cohesive, capable team” formed during Rimpac 2026 highlighted what can be achieved when nations set aside their differences and focus on shared goals. His comments have been seized upon by analysts who point to this year’s exercises as evidence that Seoul and Tokyo are slowly but surely closing the gap in their defense ties.

The legacy of Japan’s colonial rule over Korea from 1910 to 1945 continues to cast a long shadow over their bilateral relations. While joint military operations can build trust, they do not provide a solution for resolving complex historical and cultural issues. Rimpac has long been seen as a means of strengthening alliances, but this year it showed that even unlikely nations can find common ground when it comes to shared security concerns.

Seoul and Tokyo have found themselves increasingly reliant on US military support in recent years as they navigate the complex security landscape in East Asia. As China’s military footprint grows in the region, their need for cooperation on defense has never been more pressing. Rimpac 2026 serves as a reminder that nations can find common ground when it comes to shared security concerns.

However, it would be premature to declare that Seoul and Tokyo are poised to become close allies anytime soon. Their relationship remains fragile, marked by occasional clashes over issues such as trade, history, and the deployment of US military assets in their region. Joint military operations may help build trust, but they do not provide a panacea for resolving these complex issues.

As the dust settles on Rimpac 2026, attention will turn to what this means for Seoul and Tokyo’s future cooperation on defense. Will their participation at next year’s exercises be just as seamless? Or will historical tensions resurface, threatening to derail progress made so far? Only time will tell. What is certain, however, is that Rimpac has provided a much-needed boost for bilateral relations between two countries whose shared security concerns demand close cooperation.

The success of Rimpac 2026 highlights what can be achieved when nations set aside their differences and focus on shared goals. Yet, it also raises important questions about how far these nascent ties can extend in the face of deep-seated historical animosities. As the region continues to navigate the complex security landscape in East Asia, Seoul and Tokyo’s ability to put aside their differences will be crucial in determining the course of their future cooperation on defense issues.

Ultimately, Rimpac 2026 has provided a glimmer of hope for those who believe that even the most unlikely of nations can find common ground when it comes to shared security concerns. But as we look ahead to what this might portend for Seoul and Tokyo’s future cooperation on defense, one thing is clear: their relationship remains fragile, waiting to be tested by the challenges of a rapidly changing regional landscape.