Recent comments by U.S. President Donald Trump that arms sales to Taiwan are a "very good negotiating chip" in the United States' dealings with China are heightening anxieties on the island democracy that Beijing claims as its own. Trump made the comment in a Fox News interview with Bret Baier that aired right after the U.S. president wrapped up a high-stakes visit to China on Friday. China sees Taiwan as a breakaway province, to be...