http://p3.ifengimg.com/haina/2016_51/ba1d920801be6c9_w1086_h778.jpg

US President Barack Obama said on Friday no other bilateral relationship carries more significance than US-China relationship, and if the US-China relation breaks down, everyone becomes worse off.
"Given the importance of the relation between the United States and China, given how much is at stake, in terms of the world economy, national security... China's increasing role in international affairs, there's probably no bilateral relationship that carries more significance," said Obama here in his final news conference of the year.
"There's also the potential if that relationship breaks down or goes into a full conflict mode that everybody's worse off," he added.
US President-elect Donald Trump early this month received a telephone call from Taiwan's Tsai Ing-wen.
After the phone call, the White House reaffirmed it's firm commitment to one-China policy on several occasions.
http://p3.ifengimg.com/haina/2016_51/94201c18a0e6040_w1104_h768.jpg

From my point of view, it is universally recognize that there is only one China in the world, and both the mainland and Taiwan belong to one China. This policy is also the prerequisite for any countries to stay friends with China, no one should challenge it, China won't allow it so do the Chinese.