S INCE HE BECAME president in 2016, Rodrigo Duterte has talked loudly and often about his disdain for America, which is a former colonial power in the Philippines. But never before have his grievances translated into action. On February 11th he cancelled the Visiting Forces Agreement ( VFA ), a military pact between the two countries that enabled American troops to participate in joint exercises in the Philippines. The American embassy in Manila declared the decision “a serious step with significant implications for the US -Philippines alliance”.

It also has implications for the region’s security. The VFA adds practical weight to the two countries’ mutual defence pact, which remains in force. Scrapping it might encourage adventurism from South-East Asia’s jihadists (which worries Mr Duterte) and China (which may not). In 2017, when fighters allied to Islamic State captured the centre of the southern city of Marawi, Philippine forces expelled them with the help of intelligence gathered by American soldiers. By the same token, Philippine and American forces have conducted joint exercises in the South China Sea, where China’s expansive claims overlap with the Philippines’. The cancellation of the VFA imperils such co-operation.