will be realized he said. china has been pushing that point and tension to historic new highs. in the past week, sending nearly 150 war planes into taiwan s air defense zone forcing taiwan s fighter jets to scramble, missile systems to deploy. at some point there is going to be a miscalculation and it would be dangerous for the entire region. reporter: u.s. officials say they re concerned by the provocation here and warn china against hostile pressure. this is about china increasingly challenging american supremacy in part of the world. reporter: officially the u.s. doesn t take sides in the dispute over taiwan but just approved a $750 million arm sale to the island and reports of training, too. with american troops including a special operations unit and u.s. toirns said to be stationed on taiwan for over a year. taiwan is now seen as a central issue for