Chinese officials summoned U.S. Ambassador Nicholas Burns in the middle of the night for a meeting to protest Speaker Nancy Pelosi's trip to Taiwan. Burns was summoned to appear by Chinese Vice Foreign Minister Xie Feng, who is specifically in charge of managing China's relationship with the United States. Pelosi's visit infuriated Beijing, who repeatedly warned Pelosi not to make a stop there during her South Asia tour. Chinese officials called the visit a 'violation of the one-China principle.' In the summons, Xie stressed the 'nature of Pelosi's visit is extremely vicious and the consequence is very grave. The Chinese...