Seventy-two years ago, the Communist Party seized control of China after a bloody struggle. The defeated Nationalist government fled to Taiwan, frustrating Beijing's desire to capture the island. Since then, China has arisen as a superpower rivalling America; Taiwan has blossomed into a self-governing democracy and high-tech powerhouse with Washington's backing. Now, after decades of tenuous stalemate, there is a renewed risk of conflict. While it is impossible to know how this long rivalry will play out, in some respects the battle for Taiwan is already underway.

As Reuters reported in December, the Chinese military – the People’s Liberation Army – is waging so-called grey-zone warfare against Taiwan. This consists of an almost daily campaign of intimidating military exercises, patrols and surveillance that falls just short of armed conflict. Since that report, the campaign has intensified, with Beijing stepping up the number of warplanes it is sending into the airspace around Taiwan. China has also used sand dredgers to swarm Taiwan’s outlying islands.

Military strategists tell Reuters that the grey-zone strategy has the potential to grind down Taipei’s resistance – but also that it may fall short, or even backfire by strengthening the island’s resolve. They are also envisioning starker futures. While they can’t predict the future, military planners in China, Taiwan, the United States, Japan and Australia are nonetheless actively gaming out scenarios for how Beijing might try to seize the prized island, and how Taiwan and America, along with its allies, might move to stop it.

China has a range of tactics it might adopt, military experts say. They all carry risk for President Xi Jinping and his ruling Communist Party. They also pose different challenges for Taiwan and for the United States and its allies, principally Japan. Xi’s options include seizing Taiwan’s outlying islands, blockades or all-out invasion. Some Taiwanese military experts say Beijing's next step might be to seize the lightly defended and remote Pratas Islands in the north of the South China Sea. Any of these moves could spin out of control into war between China and America over Taiwan.

This report examines some of the conflict scenarios. It is based on interviews with close to a dozen military strategists and 15 current and former military officers from Taiwan, the United States, Australia and Japan. Some serving officers spoke to Reuters on condition of anonymity. The report also draws on articles in the US, Chinese and Taiwanese military and professional journals and official publications. In places, we have provided links to published articles and documents that shed light on Chinese, Taiwanese and US thinking.

These scenarios are, by their very nature, speculative. They are not predictions by Reuters of events to come. There is no certainty that real conflict would follow any of these trajectories. And hostilities may not erupt at all. But with tensions high, accident or miscalculation could become a catalyst for clashes at any time.

“For all sides the stakes are enormous,” said Ian Easton, a senior director of the Project 2049 Institute in Arlington, Virginia, and author of “The Chinese Invasion Threat,” a 2017 book which lays out the challenges the PLA faces in mounting an invasion and how Taiwan might respond. “A life and death game is underway, and none of the players have any way of knowing how it will end.”

A China foreign ministry spokesperson said the ministry would not comment on “hypothetical reports.” But the spokesperson added that the ruling party in Taiwan and ‘“Taiwan independence’ elements, in collusion with external forces, are constantly engaging in provocations by seeking ‘independence,’ which is the root cause of the current tense and turbulent situation in the Taiwan Strait.”

Today, under Xi Jinping, China is flashing impatience with Taiwan’s unwillingness to submit to Beijing’s rule. Xi says China’s aim is peaceful unification, but has pointedly refused to rule out the use of force.

Chinese control of Taiwan would dramatically reinforce the Communist Party’s prestige at home and eliminate the island as a viable model of a democratic alternative to authoritarian Party rule. It would also give China a foothold in the so-called first island chain, the line which runs through the string of islands from the Japanese archipelago to Taiwan, the Philippines and Borneo, which enclose China’s coastal seas.

For Beijing, success would translate into a commanding strategic position in Asia, undermining the security of Japan and South Korea, and allowing China to project power into the Western Pacific. But Beijing also has an incentive to be cautious: If America and its allies intervened against a takeover attempt, they could inflict heavy losses on an untested Chinese military that has not fired a shot in anger for decades. Defeat could weaken the Party’s hold on power.

For the American alliance, a Chinese takeover of Taiwan would be a devastating blow. At a stroke, the United States would lose its status as the pre-eminent power in Asia, according to most US and regional military experts. If America were unwilling or unable to defend Taiwan, its network of allies in the Asia-Pacific – including Tokyo, Seoul and Canberra – would overnight be far more vulnerable to military and economic coercion from China. Some might switch allegiance to Beijing, analysts say. Some might seek nuclear weapons to boost their own security.

If America did opt to defend the island, though, there is no guarantee it would defeat an increasingly powerful PLA, according to current and former senior US commanders. To counter China’s military rise, the United States is now rolling out new weapons and strategy in the Asia-Pacific.

There are indications America’s stance may be stiffening. Asked last month if the United States would come to Taiwan’s defence if China launched an attack, President Joe Biden appeared to depart from the long-held US policy of “strategic ambiguity” when he replied: “Yes, we have a commitment to do that.”

Lieutenant Colonel Martin Meiners, a spokesperson for the Pentagon, had no comment on “specific operations, engagements, or training” described in this report. But Meiners said that China had “stepped up efforts to intimidate and pressure Taiwan and other allies,” and this increases “the risk of miscalculation.”

For Japan, blocking China from gaining a foothold in its trade routes is vital. From Taiwan, the Chinese military could threaten Japan’s southern islands and dominate the sea lanes that carry its imports and exports. Top Japanese officials now publicly acknowledge Tokyo must assist the United States in defending Taiwan. Asked about the conflict scenarios, Japan’s defence ministry said it couldn’t comment “on hypothetical questions or speculation.”

In Taiwan, an overwhelming majority of the island’s 23.5 million people think of themselves as Taiwanese rather than Chinese and support closer economic and political ties with the United States, according to opinion polls and recent election outcomes. This sentiment has hardened as they watch Beijing’s ongoing crackdown in Hong Kong. President Tsai Ing-wen has repeatedly said Taiwan will defend its freedom and democratic way of life.

Taiwan’s defence ministry said in a statement that the island’s military had “drawn up relevant countermeasures and made various combat plans” regarding possible actions and attempts to invade Taiwan by the “Communist army.”

Xi has made one thing clear: Taiwan, he has said, “must be, will be” unified with China to realize his dream of a rejuvenated China, a nation that recaptures the position it held for centuries as a great Asian power.

Blockade of the Matsu Islands

After a long campaign of grey-zone warfare fails to bring Taipei to the negotiating table, Xi and his ruling Communist Party run out of patience. Public opinion polls in Taiwan show steadily increasing support for formal independence among the island's younger generation. The United States and its regional allies continue to bolster military and political ties with Taipei.

Xi and his top military commanders decide that China will impose a blockade on Taiwan’s Matsu Islands in a bid to increase pressure on Taipei to open talks on unification.

The Matsus are home to about 13,500 people. The chain of small islands and islets hugs the Chinese coast, lying about nine kilometres from the shores of China’s Fujian Province at the closest point. Communist authorities have always regarded the Matsus as part of China’s Lianjiang County. Now they plan to assert this claim.

PLA Navy ships and submarines encircle the islands and islets. Hundreds of sand dredgers, fishing boats and Chinese paramilitary ships also move in to bolster the surrounding flotilla. PLA fighters begin round-the-clock patrols over the Taiwan Strait. Taipei is warned that any Taiwanese fighters, surveillance aircraft or warships crossing the median line of the Taiwan Strait will be attacked.

Beijing also announces that no commercial or military flights to the islands from Taiwan will be permitted without the approval of Chinese air traffic control authorities. All commercial ships and ferry services from Taiwan are barred from entering the ports servicing the island group’s townships. Any passenger or supply vessels attempting to break the blockade will be seized, Beijing warns. The small Taiwanese coast guard and military garrison is now isolated and powerless to resist.

This is the opening of the fourth and most serious Taiwan Strait crisis since 1949. Taipei’s military commanders send warships and fighter jets to attack the PLA forces enforcing the blockade. With China’s overwhelming advantage in missiles, strike aircraft and warships, Taiwan’s relieving forces are wiped out long before they reach the Matsus.

As Taipei issues urgent appeals for military and diplomatic assistance from the United States and its allies, Beijing calls for immediate talks with the Taiwan government to discuss a timetable for unification.

Taiwan rejects Beijing’s demands but decides against a full-scale military campaign to break the blockade. The Matsu Islands are effectively under Communist Party rule. International tensions skyrocket as the United States and its allies apply coordinated trade and economic sanctions on Beijing.

Invasion of Kinmen

China has been conducting ​an unbroken campaign of grey-zone warfare and a blockade of the Matsu Islands. But the Taiwan government flatly refuses to open unification talks. Amid an international outcry against Beijing’s aggression, public opinion in Taiwan hardens dramatically against any form of union with China. Taiwan boosts defence spending, expands the period of conscription and requests sharp increases in military supplies and weapons from the United States. A US-led campaign to assist Taiwan includes accelerated support for the island’s program to build a fleet of modern, stealthy submarines.

Meanwhile, the PLA carefully conceals a build-up of forces trained in amphibious landings at ports along the coast of Fujian Province. The PLA also assembles airborne troops at a network of bases further inland.

President Xi and his top commanders decide that Beijing will seize the Taiwanese island of Kinmen, about six kilometres from the Chinese port city of Xiamen on the coast of Fujian Province and home to about 140,000 people.

Without warning, the PLA unleashes an artillery and missile barrage against Kinmen's Taiwanese army headquarters, barracks, defensive positions and key infrastructure targets. Chinese fighters and bombers launch strikes against Taiwanese garrison troops rushing to their defensive positions. While the bombardment continues, PLA landing craft packed with troops converge on Kinmen's beaches, and hundreds of helicopters ferry airborne troops to seize key strategic positions.

With the island’s airport under PLA control, Chinese transport aircraft land and begin disgorging troops and equipment. From naval bases on the Chinese coast, dozens of powerful Chinese warships and submarines sail into waters between Kinmen and Taiwan in a bid to block any reinforcements reaching the besieged island. Overhead, PLA fighters maintain a continual screen to prevent Taiwan's air force attacking the invasion force. PLA troops assault Kinmen’s beaches in an attempt to link up with the airborne forces inland on the island.

Taiwan's military commanders launch waves of missile strikes against ports along the Chinese coast and PLA warships near the island. Taiwan's air defence system also fires surface-to-air missiles at PLA aircraft over the Taiwan Strait. The island’s jet fighters scramble to attack Chinese fighters and bombers attacking Kinmen.

Before the United States and its allies can respond to desperate pleas for assistance from Taipei, PLA ground forces overwhelm Kinmen’s defenders. As American and Japanese naval forces steam towards the Taiwan Strait, Beijing warns they should not intervene. It calls for an immediate ceasefire so military and civilian casualties on Kinmen can be evacuated to Chinese hospitals and essential services restored. Beijing also demands that Taipei agree to talks on unification under the formula of “one country, two systems.”

Amid an international outcry, China blocks move by the United Nations to condemn its invasion of Kinmen. Xi and the top Chinese leadership hunker down to endure economic and trade sanctions, calculating Washington and its allies will not risk major war over such a small territory. Beijing's assessment is borne out when US and Japanese ships and aircraft avoid attacks on Chinese forces. But the crisis continues: Washington begins deploying more air, naval and ground forces to Asia. It accelerates arms deliveries to Taiwan and begins a global diplomatic campaign to impose a punishing technology embargo on China.

Customs quarantine

With tensions mounting over China’s extended campaign of grey-zone warfare against Taiwan and an ongoing blockade of Matsu, Taiwan continues to reject holding unification talks with Beijing. Public opinion remains strongly behind the Taipei government. The island boosts defence spending and expands the period of conscription.

Amid an ongoing international outcry, the United States steps up delivery of arms for the beleaguered island’s military: F-16 fighters, long-range anti-ship missiles, tanks, smart mines and attack helicopters. Washington also dispatches extra military advisers to assist in an urgent overhaul of Taiwan’s large but poorly trained reserve forces. After publicly confirming that it would help the United States defend Taiwan, Japan deploys army and navy units to southern islands in the Japanese archipelago for intensive amphibious landing training.

Alarmed at Taiwan’s preparations, China’s military and political leadership under President Xi Jinping decides to impose a snap customs quarantine of Taiwan in a bid to force the island’s leadership to agree to talks.

In a message to Taiwan’s trading partners, Beijing reminds them that they all acknowledge the ruling Communist Party’s claim to sovereignty over the self-governing island. In the same notice, Beijing informs the international community that it will enforce customs, maritime and airspace jurisdiction over Taiwan. China also announces the creation of an Air Defense Identification Zone (ADIZ), an area that stretches beyond a territory’s air space where air traffic controllers request incoming flights to identify themselves. The move overrides Taiwan’s existing control of its airspace.

Beijing bans all shipping from entering what had been considered Taiwan’s territorial waters without its permission. The Chinese authorities inform all airlines and shipping companies that they must have Beijing’s official approval to enter or leave Taiwan’s airspace or ports. They also insist that all flights, ships and ferries submit passenger manifestos and customs declarations to Chinese authorities.

Within 24 hours, a vast fleet of PLA Navy, coast guard and maritime militia ships deploy around Taiwan to enforce the quarantine, intercepting ships attempting to approach the island without approval from Beijing. PLA fighters and air-defence missile forces prepare to attack unauthorized aircraft entering airspace around Taiwan. Vessels heading for Taiwan are stopped and searched for weapons, military technology or other imports that would contribute to Taiwan’s defences. Bigger cargo vessels are diverted to Chinese ports for inspection.

Foreign military forces are warned they will come under attack if they attempt to approach the island. With only essential supplies of food and energy allowed through the cordon, Beijing demands that the international community refrain from interfering in China’s internal affairs. With the quarantine in place, and before the United States and its allies can intervene, Xi calls on the Taiwanese authorities to avert a looming global crisis and open immediate talks on unification.

Taipei rejects Chinese demands for talks and deploys warships and fighters in an attempt to break the quarantine. While calling for urgent assistance from the United States and its allies, it also launches land-based missile strikes on PLA warships and aircraft around the island. Chinese forces suffer some losses, but Taiwan’s efforts to keep its ports open for trade are quickly snuffed out by the PLA’s superior firepower.

With the sudden halt to all imports and exports, Taiwan faces almost immediate shortages of essential supplies, particularly energy. The island is suddenly cut off from the world. While the United States and its allies decide how to respond, Beijing offers to allow essential supplies to get through on condition that Taipei agrees to immediate talks on unification.

Full blockade

Under a tight customs quarantine, Taiwan’s government rejects Beijing’s demand for talks on unification and calls on the United States and its allies to assist in breaking China’s stranglehold. Global stock markets crash in anticipation of a wider military clash and a shortage of vital semiconductors and other key tech products from Taiwan.

With Washington warning Beijing to lift its quarantine or face military intervention, China decides to impose a full blockade in a bid to increase domestic pressure on Taipei.

Beijing bars all shipping from entering waters around Taiwan apart from PLA Navy and Chinese paramilitary vessels enforcing the blockade. Oil tankers heading to the island from the Middle East are diverted to Chinese terminals. All passenger and cargo aircraft are warned they will be attacked if they intrude into the new Air Defense Identification Zone that China has imposed over Taiwan.

Taiwanese navy vessels at sea are called on to surrender. Those that refuse are attacked and sunk. PLA warships and submarines lay mines in the approaches to all of Taiwan’s major ports. The crucial submarine data cables carrying Taiwan’s communications with the outside world are cut.

PLA warships and strike aircraft are deployed in strength to block the US and Japanese forces from approaching Taiwan. With the island totally isolated and shortages mounting, Beijing demands that Taipei open unification talks.

With promises of support from the US and its allies, Taiwan launches air and missile strikes on PLA warships and paramilitary vessels strangling its trade. The United States and its allies including Japan deploy powerful surface warships and submarines to the area around Taiwan to break the blockade. Long-range US bombers are deployed to Guam and Australia to boost allied firepower over the waters off the Chinese coast.

First to arrive near Taiwan, American and Japanese submarines begin sinking PLA warships enforcing the blockade. Carrying huge payloads of long-range anti-ship missiles, American bombers also inflict massive damage on China's surface fleet.

But China's powerful air-defence system and anti-ship missile batteries prevent America and its allies from opening Taiwan's shipping lanes and ports. Beijing also launches strikes on US bases in Japan in a bid to weaken America's capacity to respond. The clashes lead to heavy losses of warships and lives. With its blockade still in place, Beijing calls for an immediate ceasefire, offers to allow urgently needed supplies to reach Taiwan and invites negotiations with Washington in a bid to avert a full-scale war.

Rather than attempt to destroy the PLA's air-defence network with air and missile strikes on Chinese soil, attacks that could easily lead to all-out conflict, Washington and its allies decide to threaten an economic counterattack. They warn they will impose a counter blockade of their own on China's seaborne imports of energy and raw materials carried on sea lanes across the Indian Ocean and through the narrow chokepoints of the Indonesian archipelago.

Air and missile campaign

Alarmed by Beijing’s increasingly aggressive grey-zone tactics, the United States and its allies step up efforts to enhance Taiwan’s defences. Weapons sales are accelerated, munitions are stockpiled and Taiwan begins to bolster the readiness of its regular and reserve forces. Taiwan’s outmanned and outgunned military also begins to re-organize for asymmetric warfare: It disperses and conceals hundreds of lethal, long-range missiles capable of striking at the PLA’s superior force of warships, aircraft and targets on Chinese soil. The United States is also boosting the firepower of its forces in Asia, while senior Japanese leaders pledge support for America in defending Taiwan if the island comes under attack.

Xi and his top commanders decide that there is no realistic prospect of gaining control of Taiwan without conflict. And they calculate they face a narrow window of opportunity in which the PLA holds an advantage in firepower in the waters off the Chinese coast. In an era of increasing rivalry with the United States, delay could mean unification becomes increasingly difficult and exposes the Communist Party leadership to internal revolt. The Chinese economy is slowing sharply as a massive property bubble deflates, making it difficult to sustain the huge increases in defence spending that has delivered the world’s biggest military. The leadership considers but rules out limited measures including seizing outlying islands or imposing blockades. They calculate these operations are just as likely to ignite a global economic crisis and invite American intervention as a full-scale invasion. And, there is no guarantee Taiwan will capitulate.

But assessments from top planners convince Xi and his top brass that an invasion, the biggest and most complex amphibious landing ever attempted, is beyond the PLA’s capabilities. The risk of failure is great, which could threaten the Communist Party’s hold on power. Instead, Chinese leaders decide to launch a devastating air and missile attack on the island’s defences. The aim is to smash Taiwan’s military, demoralize the population and force Taipei to the negotiating table before the United States and its allies can intervene.

Without warning, PLA forces launch massive saturation attacks on key military and civilian targets. These include airfields, ports, air-defence radars, communication nodes, military command centres and headquarters, missile batteries, navy bases, major warships, key bridges, communication networks, power stations and grids, government buildings, radio and television stations, data centres and major transport arteries.

Beijing deploys missile, naval and air forces to keep the United States and its allies from sending forces to assist Taiwan. In follow-up attacks, China’s missile units, navy and air force strike at surviving Taiwanese warships, fighters and missile batteries.

With missiles and airstrikes intensifying across the island, Taiwan rushes its political and military leadership to specially prepared underground command centres and deploys its regular forces to their defensive positions, anticipating a full invasion. Reserves are mobilized.

From hangars buried deep in mountains, Taiwan’s fighters emerge to attack PLA strike aircraft. Taiwan’s air defence system, one of the world’s most advanced, also attacks the PLA air force with missiles from camouflaged and concealed batteries scattered around the island.

Taiwan’s long-range ballistic and cruise missiles strike Chinese airbases, missile battery radars and other military targets.

With Taiwan’s military heavily damaged and key infrastructure in ruins, Beijing calls for an immediate ceasefire before the United States and its allies can intervene and demands Taipei agree to negotiate arrangements for unification.

Despite the devastation, Taiwan remains defiant and flatly refuses to negotiate. It persists with mobilizing its reserves and dispersing its remaining weapons. It rushes extra troops to potential landing beaches to deter a PLA invasion. Amid a global outcry over massive casualties and hardship, the United States and its allies begin deploying forces to reinforce the island's defences.

All-out invasion 

Xi and his top commanders are convinced they are running out of time. With the world recovering from the COVID-19 pandemic that emerged in the Chinese city of Wuhan, China’s global standing is worse than at any time since the Korean War. Its pugnacious “wolf warrior” diplomacy and its ongoing grey-zone campaign against Taiwan are hardening American and international support for the island. And the Chinese leadership is convinced it has a narrow window of opportunity to unify Taiwan by force. America is strengthening its forces and alliances in Asia, and Taipei is beginning to make urgent moves to beef up its defences.

Xi and his commanders consider but rule out limited measures, such as seizing outlying islands, imposing blockades or waging an air-and-missile campaign. They calculate these operations are just as likely to ignite a global economic crisis and invite American intervention as a full-scale invasion. And there is no guarantee Taiwan would capitulate.

They decide to mount the biggest and most complex amphibious and airborne landing ever attempted. The PLA’s goal is to overwhelm the island before the United States and its allies can respond.

Without warning, the PLA launches massive air, missile and cyber-attacks on key military and civilian targets all over Taiwan. At the same time, the PLA attacks US bases in Japan and Guam with air and missile strikes in a bid to paralyze American forces and delay any intervention.

While these strikes are underway, a huge armada of PLA amphibious ships, landing craft and civilian ships from China’s vast merchant marine fleet sets sail from Chinese ports, about 130 km from Taiwan at its closest point. Aboard are hundreds of thousands of PLA troops and their heavy equipment.

As the landing force approaches Taiwan, PLA transport aircraft and helicopters mount airborne landings on Taiwan to seize key targets including airfields, ports, government buildings and command centres. These airborne landings include special forces units tasked with capturing or killing the island’s political and military leadership. Alongside the military operations, China launches psychological warfare through cyberattacks and misinformation campaigns on Taiwan’s internet and telecom networks.

After clearing mines and obstacles from the designated landing beaches, the invasion force lands along the Taiwan coast and begins to fight its way inland. Specially trained units seize the island’s key ports, repair damage from the fighting and prepare them to receive incoming reinforcements carried on merchant vessels and civilian roll-on, roll-off ships.

As the first missiles and airstrikes hit Taiwan, political and military leaders are rushed to specially prepared and hardened underground command centres. Taipei calls for urgent assistance from the United States and its allies. The island’s military goes into full mobilization and reserves head for their assembly points. Troops with their armor and artilleryman the extensive defences and fortifications around anticipated landing beaches.

From concealed and hardened positions that survived the initial onslaught, Taiwan’s military launches long-range missile strikes on the invasion armada and Chinese ports. From shelters deep inside mountains where they survived the initial bombardment, the island’s jet fighters emerge to launch strikes on the approaching invasion force and attack PLA aircraft threatening the island.

With its forces in Asia also under attack, the United States is joined by key alliance partners Japan and Australia and begins attacking the invading PLA force. American and Japanese submarines head for the Taiwan Strait to intercept troop transports and PLA warships. Extra US aircraft carrier battle groups are dispatched to Asia, while US bombers and stealth fighters launch missile attacks on PLA shipping and aircraft.

Within hours a major war is raging in East Asia.