The United States may have struck a fragile ceasefire deal with Iran, but the war has inflicted damage on U.S. relationships in Asia that were already strained after more than a year of President Donald Trump’s unpredictable approach to foreign policy. A new survey of leaders in Southeast Asian countries highlights the weakness of U.S. influence in the region, even among allies and partners.

The annual State of Southeast Asia survey report produced by the Singapore-based think tank ISEAS-Yusof Ishak Institute is hotly anticipated by regional experts, policymakers, and other opinion leaders. It surveys a range of Southeast Asian elites from academia, think tanks, research institutes, the private sector, governments, and civil society. Though it is not a complete public poll, the survey is generally considered the best gauge of Southeast Asian sentiment on a wide range of issues, including external powers’ influence in the region.

China in 2024 surpassed the United States for the first time to become the preferred partner for a majority of states in Southeast Asia, according to the survey in which participants were asked to choose between the two. (Japan, the longtime most popular state in Southeast Asia, has been preferred for years as a partner by Southeast Asian elites but cannot compare with the United States or China in terms of defense support.) The 2026 survey report [PDF] released this week showed that China was the preferred partner once again. Most survey respondents also perceive China as the most influential economic power in Southeast Asia (which is surely true); about fifteen percent say the United States is the most influential economic power.

In a new development not shown in prior ISEAS surveys, more than half of respondents now said that U.S. global leadership had become their biggest geopolitical concern. This displaced China’s “aggressive behavior in the South China Sea,” which had been the region’s top concern in 2025. (“New U.S. leadership” was the third-highest concern among respondents last year.)

“This perception demonstrates regional anxiety about inconsistencies in policy and the credibility of long-term commitments under Trump’s leadership,” the survey reported. Even in Singapore, a longtime U.S. partner, this fear was so pronounced that more than three-quarters of Singaporean respondents listed concern about U.S. leadership as their biggest worry. Malaysia, Singapore, and Thailand—a country with close trading ties, a U.S. partner, and a treaty ally, respectively—now also have massive concerns about U.S. economic influence in the region.