Until last week, the U.S. "One China" policy rarely surfaced for public discussion, and when it did, it didn't generate any heat. That all changed with a single phone call, as President-elect Donald Trump spoke with Taiwanese President Tsai Ing-Wen for a few brief minutes on Dec. 2.

That call, followed by a week of frenetic reaction from pundits, journalists and Trump's own Twitter feed, has shone a spotlight on the four-decade policy under which Washington officially acknowledges China's claim that Taiwan is part of China. The One China policy has helped create one of the largest trade relationships on the planet — now worth nearly $600 billion a year.

If Trump's appearance on this week's Fox News Sunday program was any indication, he's apparently formed the opinion that it needs to be used as a bargaining chip for any future negotiations with China.

"I fully understand the One China policy, but I don't know why we have to be bound by a One China policy unless we make a deal with China having to do with other things, including trade," Trump told Fox. "I don't want China dictating to me."

China responds

China's state media responded Monday.

"The One China policy is not for selling," said an editorial in the state-controlled Global Times. "Trump thinks that everything can be valued and, as long as his leverage is strong enough, he can sell or buy. If a price can be put on the U.S. Constitution, will the American people sell their country's constitution and implement the political systems of Saudi Arabia or Singapore?"

If Trump were to abandon the One China policy, the Global Times warned, and "publicly supported Taiwan independence and wantonly sold weapons to Taiwan, China would have no grounds to partner with Washington on international affairs and contain forces hostile to the U.S. Beijing could offer support, even military assistance, to U.S. foes."

But, like other state-run editorials, this one ultimately gave Trump the benefit of the doubt. It seemed to bend over backwards to find a suitable explanation for Trump's comments: Trump is inexperienced, Trump is being influenced by hawkish advisers, Trump is just testing the waters and likely won't act like this after Jan. 20, when — according to this logic — he'll suddenly realize how important China is to America's vitality.

So far, relative caution

The official government response came from spokesman Geng Shuang of China's Foreign Ministry.

"Upholding the One China principle is the political basis for developing China-U.S. ties," Geng patiently told foreign reporters on Monday. "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."

Geng's words were surprisingly diplomatic for a country that, in the past, has responded defensively and harshly to far more trivial matters.

"I think they will be very careful about responding because in a certain sense they are meeting a brinksman just like themselves," Sinologist Orville Schell told The Guardian. "I don't know what a brinksman or a bully does when they meet another brinksman and a bully. [Violence] would be one option, but very often one of them backs down."

With reports that Trump may choose John Bolton, a hardliner on Beijing, as deputy secretary of state, it doesn't appear the president-elect plans to back down anytime soon.

But China has spent the last decade building a formidable military that its leaders seem eager to use. Less than a week after Trump's conversation with Taiwan's president, China's military flew a nuclear-capable bomber over disputed islands in the South China Sea. Although Beijing has restrained itself to a war of words for now, it's possible that it could at some point use its newfound strength to make the idea of One China a reality.

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