An island 200 kilometres off the coast of China looms as the biggest international test of the Biden administration and Beijing’s relationship with the world. Characterised by its liberal democracy, resilient economy and the existential threat of invasion, Taiwan has lived under a cloud for more than half a century.

Its existence has seen Taiwanese and Chinese diplomats come to blows over a cake decorated with a Taiwan flag in Fiji, a Perth theatre forced to apologise to Chinese officials over a diplomatically sensitive performance and Qantas remove Taiwan from its list of country destinations.

Long a diplomatic flashpoint, it now threatens to become a military one. With Hong Kong subdued by the Chinese Communist Party, Beijing has turned its attention to the final territory not in its control under the “One China policy”, sending warplanes towards the Taiwan Strait every week in what is becoming a tense new normal for the island.

China’s President Xi Jinping has vowed that the “historical task of the complete reunification of the motherland must be fulfilled.”

Taiwan President Tsai-ing Wen has called for allies to support Taiwan. “They should remember that if Taiwan were to fall, the consequences would be catastrophic for regional peace and the democratic alliance system,” she said in 2021.

Why does China have Taiwan in its sights? What does Taiwan want? And, as tensions rise, how would the US – and Australia – be likely to respond?

Why are Taiwan and China at loggerheads?

Taiwan split from the mainland after years of civil war between two rival political forces: the Chinese Communist Party and the Kuomintang. The Kuomintang fled to Taiwan in 1949, along with 2 million civilians. It established a government in Taipei after the Chinese Communist Party’s leader, Mao Zedong, proclaimed the founding of the People’s Republic of China in Beijing.

China has never recognised Taiwan’s government and has set a deadline of 2049 for unification of the mainland with the island.

Taiwan’s government also claimed China as its territory under its constitution in 1949, creating a diplomatic minefield for foreign governments. The United Nations recognised Taiwan’s claim until 1971, before switching to China as diplomatic relations were established with the Chinese Communist Party.

“Taiwan has not for one single second belonged to China,” says the former co-chair of Taiwan’s Foreign Affairs and Defence Committee, Wang Ting-yu. “The Chinese Communist Party never had a single cent of tax paid from Taiwan but the past 40 years they have been using their diplomatic tactics and military threats to disturb Taiwan’s society.”

The Taiwanese Public Opinion Foundation found support for official independence for Taiwan, which could involve relinquishing its claim to the mainland in the constitution, had reached its highest level in July 2020. Some 54 per cent of respondents said Taiwan should become officially independent while 23.5 supported maintaining the status quo. Only 12.5 per cent supported unifying with the mainland.

By July 2021, support for formal independence had fallen to 46.6 per cent. Those supporting unification also dropped to 11.1 per cent, while those in favour of maintaining the status quo rose to 26.4 per cent.

But the Taiwanese government has maintained an ambiguous position on its international status, to keep the peace. The government has preferred to defend the status quo, which means it operates separately from China rather than pushing for a formal declaration of independence from the mainland which could trigger a military response from Beijing.

In January 2021, China’s Ministry of National Defence spokesman, senior colonel Wu Qian, issued a stern warning to anyone considering going further. “We solemnly warn these Taiwan separatists: those who play with fire will get burnt, Taiwan secession means war,” Wu said.

“Those who play with fire will perish by it. It is hoped that the US will be clear-eyed about this.”

That warning has since been repeated by Xi. “Those who play with fire will perish by it,” Xi told US President Joe Biden in a phone call between the two leaders in July 2022. “It is hoped that the US will be clear-eyed about this.”

Tension between the US and China ratcheted up the following month during a trip to Taiwan by US House Speaker Nancy Pelosi, which triggered rounds of military exercises by China in the Taiwan Strait and the South China Sea and raised fears of an accidental conflict between the two superpowers. Pelosi, who is second in the line of US presidential succession, was the highest-ranked US official to visit Taiwan in decades. Her visit was seen by Beijing as a de-facto endorsement of Taiwan’s government. In Washington, both Democratic and Republican representatives viewed it as a test of US resolve to support Taiwan and resist Beijing’s intimidation.

Is Taiwan a country?

That depends on who you ask. Australia has not recognised Taiwan as an independent nation since it established diplomatic relations with Beijing in 1972, which stipulated that the Chinese government had legal sovereignty over Taiwan and acknowledged Taiwan was a province of China.

Only 14 countries recognise Taiwan as an independent government, Nauru, Palau and Belize among them. For their trouble, they have no diplomatic contact with China, the world’s second largest economy. In September 2019, under the promise of economic investment and aid, Kiribati and the Solomon Islands switched their allegiance to Beijing.

Taiwan’s status is both fundamental to its government and its people at the same time as its proximity to an increasingly assertive China puts it in a geopolitical pincer. The difficulty that has plagued the foreign policy of governments around the world is how they defend a country that they do not recognise.

The island’s status as a liberal enclave in the mouth of an authoritarian state may become more important than any diplomatic label. It is now the democratic frontier.

What’s the relevance of Taiwan’s location?

Apart from its symbolic stature, Taiwan’s geographic position makes it vital to the defence of East Asia and the South China Sea.

Japan, when it occupied Taiwan between 1895-1945, used the island to launch attacks on the Philippines and Indonesia at the same time as it bombed Pearl Harbour during World War II. The island gives critical access to the Taiwan Strait, one of the world’s busiest shipping lanes, and also allows submarines to be launched directly into deep waters, opening the door to the Pacific and the South China Sea.

Joseph Bosco, a former China desk officer for the US Secretary of Defence, says China’s coastline in the East China Sea lacks deep-water ports. “Its submarines must operate on the surface until they are able to submerge and dive deep when they reach the area of the Ryukyu archipelago [near Japan],” he noted for The Diplomat back in 2015. ”If China controlled Taiwan, its submarines would have a far easier exit from Taiwan’s deep-water ports into the Pacific.”

Is Taiwan the next Hong Kong?

Hong Kong was handed back to China in 1997 after colonial occupation by the British. It was guaranteed a high degree of autonomy in its executive, legislative and independent judicial power but China has been accused of breaching the handover treaty by instituting national security laws that effectively wipe out Hong Kong’s political opposition. The laws, which followed more than a year of protest over Beijing’s rising influence, were able to be implemented because Hong Kong’s government and its police force were complicit in the crackdown on the semi-autonomous region’s pro-democracy movement.

Taiwan, where President Tsai Ing-wen won a landslide election on a platform of remaining separate from China in January 2020, is a very different proposition.

Mark Harrison, a Taiwan expert from the University of Tasmania, says public opinion remains resolute. “The people of Taiwan have been pursuing self-determination for more than a hundred years and Beijing’s actions won’t alter that long-standing historical aspiration,” he says.

Unlike Hong Kong, where China avoided sending in tanks to suppress dissent, taking Taiwan by force may be Beijing’s only option if it is to meet its target of “reunification”.

Lowy Institute fellow Natasha Kassam says even the word “reunification” is itself a product of China’s propaganda department. Taiwan, since it split from the mainland in 1949, has never been under the control or jurisdiction of the Chinese Communist Party. “China tries to make others use reunification to make Taiwan’s seem inevitable to the outside world,” she says. “But unification or even annexation is more accurate.”

China’s Ministry of Foreign Affairs regularly makes its position on the “Taiwan question” clear. “There is but one China in the world, and the Taiwan region is an inalienable part of the Chinese territory,” Foreign Ministry spokesman Zhao Lijian said in mid-January 2021, days after the People’s Liberation Army flew dozens of fighter jets over the Taiwan Strait.

“China is determined in safeguarding national sovereignty and territorial integrity, and opposing ‘Taiwan independence’ and interference by external forces.”

Why is China threatening Taiwan but not attacking?

Military sorties across the median line that splits the disputed zone are becoming more persistent and more aggressive. Each time a Chinese plane crosses the line, a Taiwanese plane is scrambled to meet it. Taiwan’s former national defence minister, Yen Teh-fa, estimated this cost $1.2 billion in 2020 alone.

The tactics are part of what is known as “grey zone warfare” where the goal is to wear down opposition rather than spark an immediate conflict. Tactics also include cyberattacks, propaganda and infiltration of pro-independence sentiment. “You say it’s your garden but it turns out that it is your neighbour who’s hanging out in the garden all the time,” Taiwan’s former military commander Admiral Lee Hsi-ming told Reuters in 2020. “With that action, they are making a statement that it’s their garden – and that garden is one step away from your house.”

China’s Overseas United Front Work Department has since updated its regulations for Chinese citizens living abroad, urging them to work within their communities to rally against pro-Taiwan forces. It “implored its overseas citizens to curb Taiwan independence” and safeguard the core interests of the country.

Wang, the former Foreign Affairs and National Defence Committee co-chair, said in the short term the greatest risk was the psychological threat of China’s grey-zone tactics undermining confidence in Taiwan’s own defence. “They can harass us, they can attack our remote islands and fire some missiles to scare the stockmarket but if the Taiwanese psychological defensive line breaks, that is another scenario,” he says.

Taiwan’s Foreign Minister Joseph Wu said in January 2022 that Taiwan’s military, political and psychological resolve was vital to its defence. “If you bow or if you show weakness, the Chinese will come with more pressure until you break,” he said. “We don’t want to do that. We want to let the Chinese understand that their pressure against Taiwan is having the opposite effect.”

The next five years are crucial. Why?

China has been rapidly expanding its military and naval power.It has more than 1 million members of its armed forces (to Taiwan’s 150,000), more than 5800 tanks and 1500 fighter jets.

But Wang said, on Taiwan’s estimates, the People’s Liberation Army still does not have enough firepower to mount a successful invasion and occupation of Taiwan for at least the next five years.

Mark Milley, chairman of the US Joint Chiefs of Staff, said in July that China could be prepared to act by 2027.

China does not yet have the number of tank landing ships required to land on Taiwan’s beaches, traverse hostile terrain, occupy and hold the capital Taipei, which is surrounded by mountains. There are only a dozen beaches suitable for invasion of that scale and only 37 ships available at this point. The Taiwanese defence force has spent decades building up these beaches against this threat, making any potential invasion bloody and costly.

“ ... taking Taiwan backed up by a well-prepared US military is a far different proposition.”

The US is also bolstering its arms sales to Taiwan in an attempt to keep up with China’s expansion. The goal is to offer enough protection to at least act as a deterrent. In one deal, it sold $2.4 billion worth of rocket launchers, artillery and missiles to Taiwan in 2020.

“China would have to ferry and sustain by sea and air an army large enough to seize and hold an island with 24 million people,” the US former deputy assistant secretary of defence Elbridge Colby wrote in The Wall Street Journal in January 2021.  “This might be feasible if the PLA attacks a Taiwan standing alone. But taking Taiwan backed up by a well-prepared US military is a far different proposition. Amphibious invasions against a capable, prepared defence are very hard.”

How would the US respond if there was an attack?

Weeks before the end of the Trump presidency, the US government declassified a key document decades before it was due to be made public: its Indo-Pacific strategy.

The document says the US will devise and implement a defence strategy capable of: “(1) denying China sustained air and sea dominance inside the ‘first island chain’ in a conflict; (2) defending the first island chain nations, including Taiwan; and (3) dominating all domains outside the first island chain.”

“The defence of Taiwan is in our own hands, and we are absolutely committed to that.”

But despite the reassurances from the top military brass in the US under the Trump and Biden administrations, Taiwanese officials were shaken by the sudden US withdrawal from Afghanistan in August 2021. The message received in Taipei was that the US would not provide military support to a government that would not defend itself.

Wu, Taiwan’s Foreign Minister, has repeatedly stated Taiwan would “fight to the end”. “The defence of Taiwan is in our own hands, and we are absolutely committed to that,” he said in October 2021.

That position was reinforced by Russia’s invasion of Ukraine in February 2022, where resistance by Ukrainian fighters has been supported by Western sanctions and billions of dollars in weapons.

After his election win in 2020, Biden maintained his commitment to Taiwan was “rock solid”. In October 2021, Biden went further by suggesting the US would intervene militarily if Taiwan was attacked by China. The comments were later walked back by the White House, which maintained that the US policy of ambiguity on whether it would defend Taiwan had not changed.

Then in May, Biden responded “yes” when he was asked by CNN if the US would defend Taiwan.

Here is the White House transcript:

CNN’s ANDERSON COOPER: “So, are you saying that the United States would come to Taiwan’s defence if —

THE PRESIDENT: Yes.

MR. COOPER: — China attacked?

THE PRESIDENT: Yes, we have a commitment to do that.”

The White House later had to once again clarify that the official US position had not changed, but analysts remain split over whether Biden was deliberately muddying the waters to keep China guessing over Washington’s plans to respond to a crisis.

The Labor government has not indicated whether it will or will not support military action if there is a war over Taiwan, but if conflict erupts it will have to think quickly about how it responds.

The exchange in October 2021 prompted former Australian defence minister Peter Dutton to state it would “be inconceivable that [Australia] wouldn’t support the US in an action if the US chose to take that action”.

The Labor government has not indicated whether it will or will not support military action if there is a war over Taiwan, but if conflict erupts it will have to think quickly about how it responds.

How would Australia respond?

The communiqué from the Australia-US Ministerial Consultations in July 2020 pledged that “recent events only strengthened their resolve to support Taiwan”. The former head of the Australian Strategic Policy Institute Peter Jennings says the Department of Foreign Affairs is no doubt thinking through what that means. “It should hurry up as the pace of events is quickening. Whatever Biden does about Taiwan, he will expect Japan and Australia to be there,” he says. “There is no exit strategy from our own region.”

Harrison agrees with Jennings. If conflict were to erupt, Australia would be expected to join. “As an ally of the US, Australia would be under very significant pressure from Washington to support any US military action in the Taiwan Strait,” Harrison says. “The Biden administration has also clearly signalled its intention to act in partnership with its allies.“

The $90-billion AUKUS deal between the US, UK and Australia, which will provide Australia with nuclear-powered submarines capable of patrolling the Taiwan Strait by the 2030s, entrenched Australia’s role as a key alliance partner in the Indo-Pacific.

“Taiwan is an island and a vibrant democracy of 24 million people. Does that ring any bells?”

Former Australian Defence intelligence official Paul Dibb

Paul Dibb, a former Australian Defence intelligence official, says the assumption of Australian support in any defence of Taiwan has been locked in for decades.

“Taiwan is an island and a vibrant democracy of 24 million people. Does that ring any bells?” he asks.

“The real point is that, in the event that American troops are being killed across the Taiwan Strait and we don’t offer to support America, the future of the ANZUS treaty will be at risk.”

He met with President George W. Bush’s deputy secretary of state Richard Armitage in the early 2000s. Armitage gave him a simple message.

“If American marines are dying in the Taiwan Strait, you better well f------ join us.”

This piece was first published in January 2021 and has since been updated to reflect developments.

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