Philippine President Rodrigo Duterte attends a welcome dinner at the ASEAN Summit in Vientiane, Laos September 6, 2016.

If you’re a historic U.S. ally under mounting pressure from an emerging superpower like China, it’s probably not a good idea to use a crude sexual epithet to describe the American president. Filipino leader Rodrigo Duterte, though, is far from a normal president. And his behavior – and that of his government – is increasingly posing a serious challenge to Washington on an ever-growing variety of levels.

Washington’s relations with the Philippines have always been complex. The Philippines were one of the very few U.S. colonies overseas before they were granted independence in 1946, although the United States retained several sovereign bases. With the rise of China and growing confrontation in the South China Sea, most experts believed links would become notably stronger – indeed, that assumption was one of the linchpins of U.S. thinking, particularly after the Obama administration announced its “Asia pivot” in 2012.

The election of President Duterte in May this year, however, has made that relationship increasingly difficult, if not outright impossible. So far, the geostrategic implications of that move have been limited. But the longer he stays in office – and the worse his relations become with the United States in particular and the broader international community in general – the starker they will become.

http://uk.reuters.com/article/us-obama-philippines-commentary-idUKKCN11C2LK