Report
Southeast Asia Influence Index - Key Findings Report
The Southeast Asia Influence Index maps the landscape of geopolitical influence in this crucial region. Building on an existing body of data-driven research by the Lowy Institute, this new project is the first comprehensive assessment of the influence of major powers in the eleven countries of Southeast Asia.
30 September 2025
Key Findings
- China is everywhere in Southeast Asia: China is a consistent presence across every Southeast Asian country. It is the region’s leading, but not dominant, external partner.
- America’s two faces: The United States is the second-most influential partner for the region, but its influence varies wildly. The Trump administration’s policies will further erode US influence in
Southeast Asia. - Southeast Asia’s collective dynamic: Collectively, Southeast Asian countries are more important to each other than to any external partner. Intra-regional dynamics, especially relations between direct neighbours, often matter more than competition among external powers.
- Japan leads the Indo-Pacific powers: Beyond the United States and China, four Indo-Pacific powers — Australia, India, Japan, and South Korea — exercise influence in Southeast Asia. But only Japan has a multidimensional presence across the entire region.
- Long-distance relationships: Southeast Asia’s next tier of partners from outside the region — Canada, France, Russia, and the United Kingdom — are peripheral players. Yet when focused tightly on geographic or thematic areas of strength, these countries can exert sharp influence.
- Diversification with dependence: No Southeast Asian country is within the uncontested sphere of influence of a single external partner, but several countries are highly exposed to China in specific sectors such as tourism, investment, or trade.
