Southeast Asian nations continue to try and avoid choosing sides between China and the United States. However, a more volatile geopolitical environment is making this balancing act increasingly difficult to maintain.

For years, Southeast Asian countries have preferred to avoid taking sides between China and the United States. This year’s State of Southeast Asia survey shows that this approach still holds, but a more contested geostrategic environment is making it harder to sustain. The region continues to feel uneasy about China’s entrenched influence, is increasingly troubled by US leadership under President Donald Trump and is more conscious of Asean’s institutional constraints. The weakening of confidence...