Recent confirmation of a U.S. troop presence in Taiwan marks an escalation in U.S.-China and cross-strait tensions, but doesn't significantly change Beijing's calculations regarding whether to take military action against Taiwan . Taiwanese President Tsai Ing-wen confirmed in an interview with CNN on Oct. 27 that U.S. troops were present in Taiwan for a training mission, though Taiwan's defense minister soon clarified that U.S. troops are not garrisoned in Taiwan. In response, China's defense minister said that if U.S. efforts to "contain China" via Taiwan continued, China would "resolutely counter and fight back." Despite these strong words, rumors of U.S. troops in Taiwan have circulated for a year, and given China's wealth of intelligence assets in Taiwan, it is highly likely Beijing already knew about this development. If the U.S. training mission truly crossed a red line, China probably already would have taken military action.