taipei taiwan assure unite state intention cause trouble taiwan strait self-ruled island envoy summit asia-pacific leaders say monday comment jam soong come tell reporters vietnamese city danang weekend good exchange u.s. president donald trump secretary state rex tillerson informal moments summit events want create trouble taiwan strait lead u.s. china japan observers think troublemaker whole world hope taiwan troublemaker soong say response question interactions trump tillerson hope use peaceful mean solve relevant problems soong also say natural interaction chinese president xi jinping relations beijing taipei nosedive since president tsai ing-wen elect last year china believe want formal independence taiwan red line beijing part tsai say want maintain peace china defend taiwan democracy security china suspend regular dialogue mechanism taiwan since tsai come power step military exercise around island also increase diplomatic pressure win another two island dwindle number diplomatic ally soong chairman china-friendly people first party emphasize summit tsai repeatedly talk seek peaceful relations stability china month xi tell trump beijing taiwan important sensitive issue sino-u.s. tie taiwan tell u.s. want cause trouble taiwan strait