Shoring up Asean unity

As US interest wanes, Japan must help build 'collective resilience', says former ambassador, writes Karnjana Karnjanatawe

- Karnjana Karnjanatawe

As China's regional influence continues to expand, Japan faces the challenge of balancing strategic priorities within the Association of Southeast Asian Nations (Asean). Amid concerns over weakening regional unity and the United States' declining engagement, Tokyo seeks to strengthen partnerships with key nations while maintaining relations with all member states.

Masafumi Ishii, director of the Resona Research Institute, a think tank and consulting firm, and former Japanese ambassador to Indonesia, discusses Japan's evolving geopolitical approach, resource limitations, and the critical role of human capital in sustaining Southeast Asia's stability and prosperity.

What is your main concern about Asean today?

My foremost concern is the weakening unity within Asean. There is no clear leadership to strengthen cohesion. Without unity, Asean loses both its strength and influence.

Internal disputes — such as border tensions between Thailand and Cambodia, and the Myanmar crisis continue to undermine regional solidarity. I believe Indonesia, as the largest and historically most influential member, should take the initiative to rebuild Asean's collective leadership.

How is the United States' behaviour affecting the region's stability?

The United States appears to be losing interest in maintaining peace and prosperity in Southeast Asia. Instead of supporting free trade, it imposes reciprocal tariffs a poor way to make friends.

What worries me more is that Washington seems to be dismantling the very rules-based order it built after World War II. Without that order, there can be no lasting peace or stable growth.

We will make every effort to maintain the United States' interest in the region because we need to keep the United States' attention. But at the same time, we need to face the reality, which is some kind of vacuum created by the withdrawal of the United States.