One of the first foreign policy moves from president-elect Donald Trump was to talk with the president of Taiwan about our two countries' "close economic, political, and security ties" that exist between Taiwan and the United States. That might sound all fine and dandy, but it had never been done by a president or president-elect since 1979, since China does not allow official relations between the United States and Taiwan.

As you might expect, China isn't too happy with the president-elect. On Monday, they expressed "serious concern" that Trump might not uphold the nation's standard "one China" policy regarding Taiwan, Reuters reports. Days earlier, on Thursday, China flew a nuclear-capable H-6 bomber over the South China Sea and "dozens of disputed Chinese islands," two U.S. officials told Fox News—a kind of flight that hasn't occurred since March 2015. The "dramatic show of force" was intended to "send a message," Fox News reports.

On Sunday, in an interview with Fox News' Chris Wallace, Trump defended his call with Taiwan's president and went even further, saying he does not feel "bound by a one-China policy"—a policy that's been in place for nearly four decades.

Since 1979's Taiwan Relations Act, the U.S. officially "does not support Taiwan independence," according to the State Department. The State Department officially recognizes that the People's Republic of China is "the sole legal government of China," and that there's only "one China and Taiwan is part of China." With that said, America and Taiwan, the U.S.'s ninth-largest trading partner, do "enjoy a robust unofficial relationship," which is "in line with the U.S. desire to further peace and stability in Asia." 

In response to Trump's comments appearing to dismiss the long-held policy, Chinese Foreign Ministry spokesperson Geng Shuang said, "I want to stress that the Taiwan issue concerns China's sovereignty and territorial integrity, and involves China's core interests." He continued, "Upholding the 'one China' principle is the political basis for developing China-U.S. ties. If this basis is interfered with or damaged then the healthy development of China-U.S. relations and bilateral cooperation in important areas is out of the question."

According to the Associated Press, Geng added, "We urge the new U.S. leader and government to fully understand the seriousness of the Taiwan issue, and to continue to stick to the one-China policy."