The Washington Post's Jia Lynn Yang explains the back story on relations between the U.S., China and Taiwan and the ramifications of Friday's telephone call between President-elect Donald Trump and Taiwanese President Tsai Ing-wen. (Alice Li,Victoria Walker/The Washington Post)

Why is a single phone call attracting so much attention?

With a roughly 10-minute phone call with Taiwanese President Tsai Ing-wen on Friday, President-elect Donald Trump broke from nearly 40 years of U.S. policy in Asia and probably complicated relations among the United States, China and Taiwan — all more than a month before assuming office.

But what, exactly, happened, what was discussed, and why are people making a big deal about it?

What did Trump and the Taiwanese president discuss?

On the call, Trump and Tsai congratulated each other on winning their elections, a three-sentence statement from Trump’s transition office said.

“During the discussion, they noted the close economic, political, and security ties exists [sic] between Taiwan and the United States,” the statement said.

A statement from the Taiwanese president’s office went into further detail, noting that the call took place Friday (at 11 p.m. Taiwan time and 10 a.m. Eastern time) and lasted more than 10 minutes. It included discussion about economic development and national security, and about “strengthening bilateral relations.”

Tsai expressed admiration for Trump’s success in a highly competitive election, the statement said.

Tsai told Trump she hopes the United States will continue to support more opportunities for Taiwan to participate in international issues, the statement said. She was also joined on the line by Taiwan’s top national security and foreign ministry officials.

Who initiated the phone call?

Even this is unclear right now. After the Financial Times and the Taipei Times first reported the phone call Friday, Trump tweeted that it was Tsai who had called him.

A follow-up tweet an hour later seemed to imply that he had simply picked up the phone to receive a congratulatory call.

But Tsai’s office later said the call was arranged in advance by both sides.

The Taipei Times reported that “Taiwan-friendly members” of Trump's campaign staff arranged the call after he was briefed on Taiwan-China relations, leading to much speculation about who that could have been.

The Washington Post reported Sunday night that the call "was an intentionally provocative move" that was "the product of months of quiet preparations and deliberations among Trump’s advisers about a new strategy for engagement with Taiwan that began even before he became the Republican presidential nominee, according to people involved in or briefed on the talks."

The call, The Post reported, "was planned weeks ahead by staffers and Taiwan specialists on both sides, according to people familiar with the plans."

As The Post wrote Sunday: "Several leading members of Trump’s transition team are considered hawkish on China and friendly toward Taiwan, including incoming chief of staff Reince Priebus.... Edward J. Feulner, a longtime former president of the Heritage Foundation, has for decades cultivated extensive ties with Taiwan and is serving as an adviser to Trump’s transition team."

Alex Huang, a spokesman for Taiwan's presidential office, described the call to media outlets as a “friendly” conversation and went a step further, adding: “Cross-strait relations [between Taiwan and China] and a healthy Taiwan-U.S. relationship can be pursued in parallel, and there is no conflict.”

It is worth noting that, since Election Day, Trump already had spoken with several other prominent Asian leaders, such as Chinese President Xi Jinping and Japanese Prime Minister Shinzo Abe.

Why is a single phone call attracting so much attention?

From 1979 up until Friday, no U.S. president or president-elect had spoken directly with a Taiwanese president, either in person or by phone.

Why? The United States agreed when it opened diplomatic relations with China in 1979 that it would break off formal ties with Taiwan, a self-governing democratic island that China considers part of China (more on this below). For nearly four decades, the United States has maintained highly choreographed unofficial relations with Taiwan, to avoid the risk of angering China, a growing military and economic power and the United States' top trading partner.

China's hypersensitivity to questions about Taiwan's status cannot be overstated.

“The Chinese rarely overlook what they perceive a potential alteration in U.S. policy toward Taiwan,” Jeffrey Bader, President Obama's former top adviser on Asia at the National Security Council, wrote in an essay for the Brookings Institution. “A look back at their conduct in 1995, when they undertook ballistic military exercises that threatened Taiwan in the wake of an unprecedented U.S. invitation to Taiwan’s president to speak at Cornell University, illustrates the Chinese mind-set. We may neither like nor admire this, but we cannot ignore it.”

About a month ago, reports emerged that a state-run bookstore in Shanghai had unwrapped a batch of Merriam-Webster's English dictionaries and torn out the page in each one containing a definition of Taiwan it did not agree with.

Censorship is not the only way that Chinese nationalists protect their interests on sensitive issues such as Taiwan and Tibet.

In January, a 16-year-old Taiwanese singer from a South Korean girl band was forced to make a humiliating video apology to China after she faced a storm of protest on Chinese social media for daring to hold a Taiwanese flag on Korean television.

Outgoing Taiwanese President Ma Ying-jeou said at the time the singer had done nothing wrong and called the episode “unjust and unacceptable.”

Why is the Taiwan-China relationship so complicated?

To understand Taiwan and China's tenuous relationship, one needs to go back more than 100 years, when the last imperial dynasty to rule China, the Qing, ceded the island of Taiwan to Japan in 1895.

In 1911, the Qing dynasty ended and the Republic of China was established. In 1927, the Chinese Civil War broke out between the Nationalist (Kuomintang) Party and the Communist Party.

Meanwhile, upon Japan's surrender in World War II in 1945, the island of Taiwan was returned to Chinese control.

In 1949, Chiang Kai-shek and the Nationalists lost the Chinese Civil War to Mao Zedong's Communists, causing Chiang, the Kuomintang party and the government of the "Republic of China" to flee to Taiwan. On the mainland, Mao established the People's Republic of China.

The People's Republic of China considers Taiwan part of China and has asserted over the decades that the island will one day be unified with the mainland.

Taiwan today functions as a multiparty democracy, having held its first free presidential elections in 1996. It is the United States' ninth-largest trading partner, according to the State Department, and the world's 18th-largest economy, after Australia, according to a 2014 report prepared for U.S. lawmakers by the Congressional Research Service.

Tsai expressing hope that the United States would continue to support more international opportunities for Taiwan coincides with Taiwan's lobbying in recent years for inclusion in everything from the United Nations to international aviation regulatory bodies — to Beijing's chagrin.

For years, it has looked like a losing battle. Taiwan is not recognized by the United Nations, having lost its seat in 1971 when the United Nations chose to recognize the People's Republic of China. Fewer than two dozen countries, including Vatican City, maintain formal diplomatic relations with Taiwan as “the Republic of China.” At the 2016 Olympic Games in Rio de Janeiro, athletes from Taiwan once again had to compete under the team name “Chinese Taipei,” a distinction that was made to appease China but that has aggravated some in Taiwan.

The phone call constituted a major and unexpected coup in the face of Taiwan's uphill struggle to get recognition on a global level.

What is the United States' role in the China-Taiwan issue?

As mentioned earlier, the United States maintained diplomatic relations with Taiwan until 1979, when it opened formal diplomatic relations with China. One major stipulation for doing so was a U.S. acknowledgment of China's position that “there is but one China and Taiwan is part of China,” and therefore breaking off its official ties with Taiwan, as it could only recognize a single government of “one China.”

However, the United States could continue to maintain unofficial ties with Taiwan, and has done so through the decades. In April 1979, the U.S. Congress passed the Taiwan Relations Act “to help maintain peace, security, and stability in the Western Pacific” and to continue “commercial, cultural and other relations” with Taiwan.

The act stressed that U.S.-China relations rested on the expectation that the future of Taiwan “be determined by peaceful means” and allowed for U.S. arms sales to Taiwan for the purposes of defense. The Taiwan Relations Act also established the American Institute in Taiwan, a nonprofit corporation with offices in Taipei and Arlington, Va., that implements U.S. policy toward Taiwan. The AIT in effect serves as an unofficial embassy, with its director filling the role of an unofficial U.S. ambassador to Taiwan.

In the process, the United States has shaped and abided by its own “one China” policy (not to be confused with China's “one China” principle), in which Taiwan's status remains neither settled nor challenged. (The official language in a joint 1972 communique states that “the United States acknowledges that Chinese on either side of the Taiwan Strait maintain there is but one China and that Taiwan is a part of China. The United States does not challenge that position.")

The State Department's page on Taiwan notes that “the United States and Taiwan enjoy a robust unofficial relationship.”

Since 1979, U.S. engagement with Taiwan has been dictated by the Taiwan Relations Act, including sales of some weapons. In recent years, arms sales have included more than $5 billion in upgrade kits for Taiwan's F-16 fighter fleet in 2011. In December 2015, the U.S. government announced a $1.8 billion arms sale to Taiwan that would send high-profile defense items such as warships and surface-to-air missiles to help bolster the small island nation’s military.

The announcement drew sharp criticism from China, but State Department spokesman Dave McKeeby said then the sale was consistent with U.S. support for Taiwan to defend itself under the Taiwan Relations Act.

Who is Tsai Ing-wen and why is her role in this phone call particularly noteworthy?

Tsai was elected earlier this year as Taiwan's first female president, garnering more than 56 percent of the vote, and took office in May. While it would have been significant had Trump spoken with any Taiwanese president, it cannot be overlooked that he spoke with this Taiwanese president: Tsai represents the Democratic Progressive Party (DPP), which favors Taiwanese independence. She replaced former Taiwanese president Ma Ying-jeou of the Kuomintang (KMT), a party that historically has promoted eventual unification, or at least closer economic ties, with China.

In the run-up to Tsai’s inauguration, Beijing pressed her to accept the idea of “one China,” a framework negotiated in 1992 — when Taiwan was under KMT governance — that allows both sides to recognize that there is one China without specifying what that means. The Chinese side calls this the 1992 “consensus,” but many DPP and Tsai supporters deny that consensus was reached.

In her closely watched inaugural speech, Tsai took a cautious line, saying that she “respects” the 1992 meetings as “historical fact,” but did not venture further. Predictably, Beijing hit back, with its Taiwan Affairs Office blasting her line as “vague” and comparing her remarks to an “incomplete answer sheet.”

What has the Chinese government's response to the Trump-Tsai phone call been?

Although Beijing has lodged an official complaint with the United States about the call, it appears that China is focusing the blame on Taiwan.

Wang Yi, China's foreign minister, said Saturday that the phone call was “just a small trick by Taiwan” that he did not think would change U.S. policy toward China. More specifically, Wang used the words xiao dong zuo to describe the phone call, presumably implying that Taiwan had initiated contact. Although the phrase literally means “small action,” it denotes a kind of sneakiness or trickery. (In writing about China's response to the phone call, The Washington Post translated xiao dong zuo to mean a “petty” move.)

“The One China principle is the foundation for healthy development of Sino-U. S. relations,” Wang said Saturday. “We don’t wish for anything to obstruct or ruin this foundation.”

But wait: Was Trump 'just' conducting his own personal business?

On Saturday, the mayor of Taoyuan, Taiwan, told local media that the Trump Organization was interested in developing a hotel there and that a company representative had visited the city in September. The sprawling Taipei suburb is also where Taiwan's major international airport is located.

These reports led to speculation that Trump had accepted the phone call for his personal business gain. The Trump Organization denied those reports Saturday.

“There have been no authorized visits to Taiwan on behalf of Trump Hotels for the purposes of development nor are there any active conversations,” a spokeswoman for the Trump Organization told CNN. “Trump Organization is not planning any expansion into Taiwan.”

What does this mean for the future of diplomatic relations under a Trump administration?

Experts on China, Taiwan and U.S. diplomatic relations have reacted in a number of ways to the phone call and its implications, ranging from apoplectic to allowing for a “wait-and-see" approach.

“My guess is that Trump himself doesn’t have clue,” said Bonnie Glaser, a senior adviser for Asia at the Center for Strategic and International Studies. “That he had no idea about Beijing’s neuralgia on Taiwan.”

Kellyanne Conway, Trump's senior adviser and former campaign manager, dispelled that notion in an interview with CNN's Anderson Cooper.

“He either will disclose or not disclose the full contents of that conversation, but he's well aware of what U.S. policy has been,” she said.

She reiterated that on “Fox News Sunday,” telling host Chris Wallace that Trump was “not making new policy.”

“He's merely taking phone calls, and he will I'm sure reengage with many of these leaders once he takes office,” Conway said on Fox.

Vice President-elect Mike Pence told “Meet the Press” host Chuck Todd on Sunday that he didn't think anything should be read into the “courtesy call.”

Still, the phone call drew immediate reactions from former officials who for years had carefully scripted and stage-managed every utterance from U.S. officials about Taiwan. Former White House press secretary Ari Fleischer noted that, under the George W. Bush administration, he wasn't even allowed to refer to the “government of Taiwan,” and instead danced around the issue by using the phrase “government on Taiwan.”

“China will go nuts,” Fleischer tweeted Friday evening after news of the Trump-Tsai phone call broke.

Douglas Paal, who served as an unofficial U.S. ambassador to Taiwan as a former director of the American Institute in Taiwan, remembered such careful choreographing well.

“Phone calls back and forth [between Taiwan and the United States] were not done; messages were not done directly,” Paal said Saturday.

If the Taiwanese president wanted to send a message to the U.S. president, for example, it would need to be routed through the AIT so as to avoid direct communication, he said. Similarly, as AIT director, Paal always referred to “authorities” in Taiwan, not “officials.”

“For now the Chinese have chosen to interpret this as a bump in the transition and a 'trick' by Taiwan,” Paal said. Although some are seizing on the issue and making it a partisan one, most experts “just want to see if this is consequential for policy. They don’t have enough information to come to that conclusion yet.”

For the incoming administration, Susan Shirk, chair of the 21st Century China Program at the University of California at San Diego, said the phone call was an “impulsive” move and a “bad sign for Trump foreign policy.”

As The Post reported Friday, most of the more than 50 calls held by Trump or Pence came without the knowledge or guidance of the State Department. That means no government talking points about issues of particular importance — or land mines to avoid.

“We stand by to assist and facilitate and support communication that the transition team is having with foreign leaders,” State Department spokesman John Kirby said Friday.

The call and Trump’s subsequent tweets raised fresh questions about who is advising the president-elect on Asia policy — and how.

Paul Haenle, who was on the National Security Council staffs of President George W. Bush and President Obama and is now director of the Carnegie-Tsinghua Center in Beijing, said the incident showed the importance of Trump taking daily intelligence briefings, consulting with experts at the State Department and Department of Defense and quickly assembling a China team.

Past administrations took a “no surprises” approach to Beijing, Haenle said. “The alternative — catching China by surprise on some of the most sensitive and long-standing areas of disagreement in our relationship — presents enormous risks and potential detriment for this consequential relationship.”

Richard C. Bush, the director for the Center for Northeast Asian Policy Studies at the Brookings Institution, said China could ignore the call down the line with respect to Trump and Taiwan or come down hard on one or the other.

“I think the scratches on the oracle bone suggest that they may be more lenient with Trump than with Tsai Ing-wen,” Bush said. “We have already seen examples of ways that Beijing is pressuring the Tsai administration because it has not complied with Beijing’s demands about the 1992 consensus.”

Still, Bush said it was too early to tell.

“I think some people are overreacting — the people who say, oh this is the end of the U.S.-China relationship as we know it. That’s not necessarily true. They could be lenient to Trump and treat Taiwan differently,” Bush said. “We need to know a lot more and we shouldn’t pre-judge the situation but we shouldn’t trivialize it either.”

Is Taiwan the same as Thailand?

No.

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