In this article in the Boston Globe on October 15, 2016, Stephen Kinzer points out that President Duterte’s grievance ‘is rooted in history’. President Duterte asserted that the US had unjustly seized the Philippines in 1899 and waged a horrific military campaign to suppress native resistance.
Stephen Kinzer is a senior fellow at the Watson Institute for International and Public Affairs at Brown University, USA. See link to article below.