On 26 May, CNN broadcast an unusual clip of a US navy intelligence flight over the South China Sea. The P-8A Poseidon surveillance plane – one of the newest weapons in the Pentagon’s arsenal – had taken off, with a CNN reporter on board, from Clark airbase in the Philippines, once part of America’s largest overseas base complex during the cold war. After about 45 minutes, the plane reached its first target – which had, until recently, been an obscure, almost entirely submerged feature in the Spratly Island group.

Fifteen thousand feet below, dozens of Chinese ships tossed at anchor. Their crews had been working day and night for weeks, dredging sand and rock from the ocean floor to fill in a stunning blue lagoon – turning a 3.7-mile-long reef that had only partially revealed itself to the daylight at low tide into a sizable man-made island nearly 1,000 miles away from the Chinese mainland.

At the approach of the American aircraft, a Chinese radio operator can be heard addressing the pilot: “This is the Chinese navy. This is the Chinese navy … Please leave immediately to avoid misunderstanding.” When the plane, which was busily photographing the land-reclamation effort, failed to heed these instructions, the operator grew exasperated, and the recording ends as abruptly as it had begun, with him shouting the words: “You go!”

China's land grab in the South China Sea China’s land grab in the South China Sea

For many people who viewed this clip, it might have almost passed for entertainment, but the plane continued on to a place called Fiery Cross, whose history and recent development point to how deadly serious the struggle over the South China Sea has become. Fiery Cross came under Chinese control in 1988, following a confrontation with Vietnam at a nearby site, Johnson Reef, where Chinese troops opened fire from a ship on a contingent of Vietnamese soldiers who stood in knee-deep seas after having planted their country’s flag in the coral. A YouTube video of the incident shows dozens of Vietnamese being cut down in the water under a hail of machine-gun fire.

China had come late to the game of laying claim to parts of the Spratly archipelago, which comprises hundreds of uninhabited coral reefs and sandbars flung across a vast area between the coasts of the Philippines and southern Vietnam, each of which has long controlled numerous positions in the area. But in this bloody way, China announced that it was fully committed. Its position on Fiery Cross Reef, staked out back in the 1980s, was initially justified under the auspices of Unesco, which had called on the nations of the world to cooperate in collectively surveying the oceans for meteorological and navigation purposes. Fast-forward 28 years, though, and as seen from the American surveillance flight, what had begun as an innocuous “ocean observation station”, has now mushroomed in less than a year of dredging into the most important of Beijing’s seven newly created positions in the South China Sea.

From a single coral head that peaked a mere metre out of the waves, Fiery Cross has grown in stunning fashion, attaining a size of over 200 hectares of reclaimed land – roughly equivalent to about 280 football pitches. Leaving little doubt about its purpose, it has already been equipped with a 3,300-metre airstrip, which is long enough to accommodate a wide range of Chinese combat and transport planes, and a harbour big enough to handle even the largest of the country’s ships.

The primary attraction of this locale, though, may be something that cannot be perceived from even the most sophisticated surveillance plane, which from China’s perspective is precisely the point. Fiery Cross appears to have been chosen by Beijing as the keystone in its push into the South China Sea because of the depths of its surrounding waters, which afford Chinese submarines far greater stealth in evading acoustic and other forms of active tracking by the US military.

Facebook Twitter Pinterest The partially built airstrip on Fiery Cross Reef in the Spratly Islands, in April 2015. Photograph: AFP/Getty Images

There is no single explanation for why asserting its authority over the South China Sea now matters so much to China. Controlling the many tiny islands is in part a matter of controlling of the wealth assumed to lay beneath the sea in the form of unexploited minerals and oil and gas, not to mention the immense fisheries that exist in these waters. It is in part a matter of increasing the country’s sense of security, by dominating the maritime approaches to its long coast, and securing sea lanes to the open Pacific. It is in part a matter of overcoming historical grievances. And finally, it is about becoming a power at least on par with the US: a goal that Chinese leaders are themselves somewhat coy about, but which is now increasingly entering the public discourse.

The best place to see all these reasons at work is the country’s southernmost province, the island of Hainan.

* * *

Right from the taxi stand at the ultramodern train station in semi-tropical Sanya, there was no mistaking how different this seaside city was going to be from the rest of China. It was late December and already frigid across the rest of the country – and even chilly in the north of Hainan island, from where my fellow disembarking passengers had all arrived.

As we joined the long queue for cabs, people busied themselves peeling off layers of clothing, and making an ostentatious show of their resortwear underneath. There were two who stood out in particular, first the buxom lady in front of me in the low-cut knockoff Gucci T-shirt, who chewed her gum with a demonstrative little snap. Then there was the guy a couple of spots behind, but seemingly joined to her by a current of energy. He appeared to be well into his 40s, but he sported a boyband haircut, and wore a skimpy singlet and conspicuous gold chain. Every time our line turned a corner, sending the herded passengers ahead of us snaking back in the opposite direction, he leaned on the guiderails, smiling as he craned for a glimpse of her breasts. These were not nouveaux riches exactly, but they were exemplars of new Chinese wealth nonetheless, a wealth that is creating a giant middle class that is yearning to do all of the things that middle classes everywhere are wont to do, and not necessarily in stages either, but rather as hurriedly as possible, and, indeed for some of them, all at once.

That, in fact, is a fairly complete explanation of Sanya’s most famous raison d’être. It is, in the new China, a bucket-list city par excellence, a purpose-built place on the southern coast of Hainan Island that is kept warm year round by the currents of the South China Sea. In the winter, huge numbers of Chinese arrive here every week, much like pilgrims, except for the fact that their god, the god of leisure and consumerism, is of very recent vintage in this country.

I, too, had come because of the sea, but not for any of its popular attractions. The beaches of Sanya have become famous among Chinese as their country’s answer to Hawaii, but this is not the only thing the place has in common with America’s 50th state. While the vacationing hordes headed off for the local version of Waikiki, long rows of fancy, newly sprouted hotels and vacation rental high-rises, I had come in hopes of getting a glimpse of the closest thing in China to Pearl Harbor.

Just as a fast-expanding US used that naval base, beginning late in the 19th century, to project American power deep into the Pacific, an ocean that it would eventually come to thoroughly dominate, China is leveraging Hainan island to press some startling claims – not to mere dominance, but for rightful possession of virtually the entire South China Sea, a body of water that encompasses 1.35 million square miles, and through which more than $5tn in ship-borne trade passes every year.

China’s neighbours have watched with growing alarm as Beijing has used maritime vessels, often setting out from Hainan, to harass and intimidate the far smaller rival claimants whose littoral territories both enclose the South China Sea and lend it definition. Recently, for example, China sent a large flotilla of ships close to the shores of Vietnam as it deployed a billion-dollar oil rig that an official of the China National Offshore Oil Corporation described as “our national mobile territory”, while it made a show of prospecting for crude in deep water. As it did so, China kept a collection of much smaller, protesting Vietnamese vessels at bay by blasting them with massive water cannons powerful enough to sink many ships. At other locations, not far away, Chinese ships have intercepted vessels from the Philippines – sometimes by deliberately ramming them – to stop them from resupplying troops who guard disputed coral reefs that lie several times closer to Filipino shores than to anything conventionally understood as Chinese territory. It was against this backdrop that China began its own crash programme of dredging the oceans to build man-made islands in at least seven locations in the South China Sea in 2014.

Facebook Twitter Pinterest The beaches of Sanya have become famous among Chinese as their country’s answer to Hawaii Photograph: Getty Images/Lonely Planet Image

But there is much more at stake in China’s plans for Hainan than the possession of a few spits of sand and rock hundreds of miles to the south. China’s coastguard, until recently very modest in size, is growing so fast that by the next decade it will boast more tonnage than the coastguards of the US, Japan and all of its south-east Asian neighbours combined. The Chinese coastguard’s ships are so large that they dwarf the platforms of many navies, blurring the lines that have traditionally distinguished these two services. And because its purpose is asserting mastery of the sea over a collection of far weaker neighbours to the south, much of this rising force will call Hainan its home.

The Chinese coastguard’s ships are so large that they dwarf the platforms of many navies

For all of its strengths, where China’s new maritime might is concerned, the coastguard is still the little league. With quite distinct purposes in mind – namely the increasingly intense security competition between Beijing and Washington – China is rapidly equipping itself with the world’s largest submarine fleet, including a new force of nuclear ballistic missile vessels. It has also launched programmes to build a fleet of modern aircraft carriers, and the full range of associated battleships. In Hawaii, 5,800 miles away, the berths of the US’s most formidable naval assets and that state’s world-famous beaches are situated in different parts of the most-visited island, Oahu. But here in Hainan, just outside of Sanya, China’s newest and most advanced naval docks and its best beaches are located practically right next to each other, and I had gone there in order to try to have a look.

* * *

China is two years into what figures to be the 10-year tenure of Xi Jinping as president and head of the Communist party; many observers already describe him as the country’s most powerful leader since Mao Zedong. The previous holder of this distinction was Deng Xiaoping, who is credited with ending Maoism, opening China to foreign investment and putting the country on a path of explosive growth that is now into its fourth decade. But even Deng had to contend with peers in the party hierarchy who were far more conservative than him. Most leaders in the post-Mao era have had to spend several years laboriously consolidating power before announcing anything that smacks of a personal agenda. As a measure of his ambition, Xi, by contrast, announced a watchword for his rule in his very first days in office, and it is one that the state media has never departed from. The new leader’s agenda would be what he called the “great dream of national revitalisation”, which is often interpreted to mean lifting China to the first rank of world powers and reclaiming for it the preeminent place that every schoolchild learns was China’s lot for the majority of recorded history.

For most of the period between Mao’s death in 1976 and the advent of Xi, China followed the adage, attributed to Deng, of “hiding one’s capabilities and biding time”. This meant, above all, deliberately keeping a low profile in the world while the country steadfastly accumulated wealth and power. From the outset, what Xi called “the China dream” put a decisive end to all that.

During his first year in power, without warning, China suddenly proclaimed a so-called ADIZ (air defence identification zone) that covers an expansive maritime area separating China from Japan and includes a hotly contested group of tiny islands, known as the Senkakus (Japanese) or Diaoyu (Chinese), which have been under largely undisputed Japanese control since 1895. China followed up on this action almost immediately with a series of gestures that seemed designed to demonstrate its restored strength to its southern neighbours. In Xi’s early days in office, the country’s first aircraft carrier, the Liaoning, which was acquired several years ago from Ukraine and then extensively refurbished, was sent with a full battle group of other warships on a maiden cruise straight into many of the most fiercely disputed areas of the South China Sea.

Facebook Twitter Pinterest China’s first aircraft carrier, the Liaoning. Photograph: China Daily/Reuters

However muscular Xi’s moves might at first appear, no one should think that he is a warmonger. China has as rich and sophisticated a tradition of statecraft as any nation, and a capacity for diplomacy of great subtlety. What the new Chinese leader has openly declared that he wants, though, is an Asia administered by Asians, and this is an idea that runs straight through Hainan island, and should be taken seriously. To grasp what it might mean requires thinking about the past as much as looking to the future.

There is nothing more central to the China dream than China’s idea of its rightful place in the world – which, Chinese people are relentlessly taught, they were robbed of first by European imperialism and then by an American-imposed Asian order that has been in place since the end of the second world war. Prior to this, for nearly the entire run of their nation’s long history, save for the occasional parenthetical setback, the Chinese understand themselves to have enjoyed well-deserved paramountcy in the vastness of the east. This has meant not just preeminence, but deference from neighbours eager to curry favour and share in the fruits of China’s brilliant culture.

“In East Asia’s tribute system, China was the superior state, and many of its neighbouring states were vassal states, and they maintained a relationship of tribute and rewards,” writes Liu Mingfu, a retired People’s Liberation Army colonel, in The China Dream, a hugely popular recent book that lays out plans for the country’s return to preeminence. “This was a special regional system through which they maintained friendly relations and provided mutual aid. The appeal and influence of ancient China’s political, economic and cultural advantages were such that smaller neighbouring states naturally fell into orbit around China, and many of the small countries nominally attached to China’s ruling dynasty sent regular tribute … The universal spread of China’s civilisation and the variety of nations that sent emissaries to China were simply a reflection of the attractiveness of the central nation, and the admiration that neighbouring countries had for China’s civilisation.”

It is true that many territories paid tribute to China, which they may have judged to be a small price for gaining access to trade with the world’s richest economy. But it is also true that China often used force to gain dominance over others, whether the Koreans or the Burmese or, most famously, Vietnam, which China occupied for 1,000 years. Through the teaching of history in this selective fashion, however, Chinese supremacy is made to appear to be the natural order of things, and never something that was forcibly imposed; hegemony, in Chinese usage, is a state of affairs that can only result from the actions of ill-intentioned foreigners.

Hegemony, in Chinese usage, is a state of affairs that can only result from the actions of ill-intentioned foreigners

Lingering threads of this kind of thought are evident in Beijing’s interactions with Japan, its only conceivable rival in the region. That status is one that a fast-rising China appears increasingly unable to abide. Similar motivations can be detected in the recent proliferation of extraordinary infrastructure schemes, in which all new roads will lead to the Rome of the East, otherwise known as Beijing. These include new transcontinental rail lines with high-speed passenger service and immense freight capacity that will completely outclass Russia’s badly aging Trans Siberian Railway, as well as the integration of south-east Asia into the Chinese rail network through Chinese-built railways in Vietnam, Cambodia, Thailand, and Laos. It also includes a maritime trade network of ports and depots that span the Indian Ocean, culminating in east Africa, an important frontier of China’s expanding interests. Under one variation or another, Beijing has called all of these “new Silk Roads”, an appellation that is meant to conjure Chinese centrality and grandeur.

As it moved on all of these fronts, in the space of a mere two years, China has astutely built from scratch a major new multilateral bank, the Asia Infrastructure Investment Bank, which will be run under its leadership, competing with such western-led institutions as the World Bank and the Asian Development Bank, to fund construction projects that will inevitably play to China’s industrial strengths. The US was caught off-guard, and perhaps feeling that its own 70-year-old imperium in Asia was threatened, responded by snubbing the bank even as 56 countries – including many old-line allies in Europe, not least Britain – rushed to join the new institution.

As immensely ambitious projects such as these proceed, the gap in wealth and power between China and its maritime neighbours will continue to widen. Beijing’s hopes for the future seem to align with the way China teaches the history of its imperial past – in which nearby states will pragmatically accept that the price of China’s favour is deference.

Still, in order to retain a sliver of legitimacy for its claims to rightful control of nearly all of the South China Sea, and to preserve the hope of a peaceful outcome in pressing these claims, China needs a respectable theory to justify them. And just as surely as it is building islands at sea, it has phalanxes of people working away to make that case.

* * *

In the bureaucratic wars that determine how Beijing allocates state resources, many players have recently discovered that invoking China’s territorial interests in the South China Sea is the equivalent of pushing on a wide-open door. By now, as a result, the task of defending China’s “sacred rights” over this body of water – a stock phrase used in official propaganda – has become something of a mad scramble.

At the top of the heap comes the People’s Liberation Army Navy, a service that has one of the fastest-growing budgets in what is already a very rapidly expanding Chinese military. Next comes the China Coast Guard, a behemoth created in 2013 by the consolidation of four law-enforcement agencies that overlapped each other and routinely engaged in ferocious rivalries. Experts say that the integration is still far from complete, and that even oversight of the China Coast Guard is split between different authorities, each with its own rival interests. There is also the Ministry of Public Security, and something called the State Oceanic Administration. And this list only accounts for the national players. Beneath them come myriad provincial agencies and actors and big private companies that claim to promote law enforcement, to supervise fisheries, to explore for oil and gas, and to promote tourism.

Probably the biggest boondoggle of all in this regard is Sansha, in the Paracel island group, which was declared in 2012 to be one of China’s almost 300 prefectural level cities – an administrative designation typically reserved for places with millions of residents. Sansha, home to all of 1,500 civilians, is located on a mere dot in the sea called Woody Island – but China moved to elevate its status immediately after Vietnam passed a law declaring ownership of the Paracels, which are also claimed by Taiwan. All told, the Paracels consist of about 130 coral islands and reefs totalling less than three square miles in surface area. China has controlled the entire group since the 1970s, when it first used force to evict Vietnamese soldiers from the islands, a decade and a half before the shootout with Vietnam in the Spratlys. Since then, in an ostentatious fit of patriotism, the Hainan government and an array of Chinese corporations have lavished investments on public works and amenities of all kinds on the island, starting with solar panels, a power grid and a state-of-the-art desalination plant. Plans are now afoot to welcome cruise ships there, so that flag-waving Chinese tourists can be lectured on their country’s inalienable rights to the region before setting off to gaze upon other rocky protuberances in the region that China claims as territory.

Many of China’s neighbours, and indeed the US, regard the assertion of its claims to tiny reefs and rocky formations located as far as 1,800 miles away from Hainan’s coast – and sometimes only dozens of miles from other coastal south-east Asian states – as a bald-faced territorial grab, something faintly reminiscent of the European-led high imperial era of the late 19th century. The search for a theory that could help distinguish China’s claims from a simple case of might makes right led me one morning to the National Institute for South China Sea Studies, in Haikou, the grey and chilly administrative capital of Hainan, to see its founding director, Wu Shicun.

I had been picked up at my downtown hotel by two young men who worked at the centre and driven in a van through the rain to their workplace, which occupies a large, verdant plot located where the town petered out. There, I was met at the entrance by a pleasant young woman named Yang Yang, who would serve as my hostess. She led me into the institute through giant wooden doors and performed a quick tour of the impressive facilities, explaining that Dr Wu was tied up, and would be with me shortly. I was immediately struck by how everything seemed built to a standard of extra-generous spaciousness, as if crowds of experts regularly gathered here, and this insistently drew one’s attention to the unavoidable fact that in room after room, there was no one around. Saddest of all, perhaps, was the capacious library, a space with a well-lit study floor full of desks, in addition, of course, to stacks, which I was told were full of volumes in both Chinese and foreign languages. There, I encountered but a single person – a rather pained-looking young librarian.

When the tour was finished, Yang asked me if I would mind watching a short film about the institute, explaining that “all the guests do”. As a photographer took pictures of me, perhaps for use in a scrapbook, the lights in the projection room were dimmed, and the movie began with images of coastguard ships ploughing through high seas, as a narrator spoke in English in a booming voice: “The advent of the ocean century brings with it unprecedented opportunities.” A blue highlight flashed onto the screen covering virtually the entire South China Sea, right up to the shores of other neighbouring states. The narrator said nothing about risks, announcing instead: “The sea is crucial to the development of China and its future as a maritime state.”

When the seance had finally ended, I was led up the stairway a couple of floors to Wu’s gigantic office, where he greeted me almost as a diplomat might, with a handshake and stiff smile from behind his large, wooden desk, his mane of silver hair swept back dramatically. I had been led to believe that my host was mightily busy, but as our conversation got under way, the impression one got in his formal, clutter-free office could not have been more different. In a meeting that lasted more than an hour, we were not interrupted, and never once did Wu check any devices for messages. The only other activity was performed by his assistant, Yang, who sat nearby throughout, taking notes.

Wu launched into a historical explanation, telling me that China was the first to discover all the tiny islands that dot the South China Sea, the first to name them and the first to assert effective control over them. “Our exercise of jurisdiction began as early as the Tang Dynasty, in the ninth century,” he said, adding “[all of these places] were under the administration of Yan County, in Hainan.”

He was not happy when I replied that I had spent the past few years studying this historical record for a book, learning – among other things – that although ships from as far away as Persia commonly travelled to China via the Malacca Strait, there is scant archaeological record of Chinese ships in maritime south-east Asian lands prior to the 15th century, not long before the first European imperialists turned up in the region, changing everything for ever. “I thought he came here to discuss the law,” he reproached his assistant sternly in Chinese.

The onset of a fever in the region around maritime issues can be traced to China’s revival of an artefact of its early-20th-century history, known as the Nine-Dash Line. This line, which made its first official appearance in 1947, under the nationalist government of Chiang Kai-shek, encloses virtually all of the South China Sea in a loop that dangles southward from the Asian mainland in a shape that has been likened to a cow’s tongue. Chiang was defeated two years later by the forces of Mao Zedong, after a long and brutal civil war, and for decades afterwards almost nothing was heard of the Nine-Dash Line. China set off alarms in the region when it began resuscitating the line early in this decade, giving it renewed prominence in state propaganda, and including it on a map contained in all new Chinese passports. At a 2010 ministerial conference of the Association of Southeast Asian Nations in Hanoi, the Chinese foreign minister responded to criticisms of its moves in the region by dressing down his Singaporean counterpart, telling him: “China is a big country and other countries are small countries, and that’s just a fact.” This created a feeling held widely in the region that despite a decade of soothing talk from Beijing about good-neighbourliness and win-win relations, China was reverting to an old form of behaviour, whether that of the wounded revanchist, or the central kingdom demanding obeisance.

Since then, after losing in a showdown with China over Scarborough Shoal, a reef located 123 miles from its shores, the Philippines has taken the lead in the region in challenging China’s sense of entitlement, bringing a case contesting the validity of the Nine-Dash Line before a tribunal under the United Nations Convention on the Law of the Sea (Unclos), and drawing repeated expressions of outrage from Beijing at its impertinence. China has vowed to ignore any unfavourable ruling by the tribunal, despite being a signatory of the convention. Similarly, Wu told me that China would not negotiate territorial issues in the sea on a multilateral basis with neighbouring states, nor would it accept outside mediation. This would leave no way forward, except for China’s much smaller and increasingly dependent neighbours to negotiate with it one on one.

Facebook Twitter Pinterest Protesters stage a rally outside the Chinese embassy in Manila demanding that China pull out of the contested Scarborough Shoal in the South China Sea. Photograph: Dondi Tawatao/Getty Images

As set in stone as these positions sounded, Beijing’s approach to control of the South China Sea has evolved in important, if subtle, ways since international public opinion, especially in the region, has turned critical of its actions. Most notably, China has seized on the vagueness inherent in the Nine-Dash Line, for which it has never attributed specific geographic coordinates, to suggest that people opposing it are tilting at windmills. “China has never claimed the entire South China Sea,” Wu told me. “China just claims sovereignty over islands, reefs and features, above water or submerged, and also to adjacent waters. If an island can sustain human life that, of course, generates an EEZ.” This term – standing for exclusive economic zone – means an area extending 200 nautical miles out to sea for China’s sole economic use. But the only justifications Wu offered for China’s claims to these features were the same historical arguments that we had already more or less agreed to disagree about, and which have no standing under the law of the sea.

This led me, at last, to ask Wu what this was really all about. Why is it so important for China to control essentially all of this body of water, extending nearly 2,000 miles from its nearest conventionally defined coastline? “The reason that this has become an important issue is geopolitics,” he replied. “The South China Sea is located at the edge of the Pacific Ocean, and this attracts the interest of many other countries – the US, Japan, India, and others.” Others have long speculated about whether China’s obsession was driven by an unproven conviction that the sea contained immense reserves of hydrocarbons, or whether it had more to do with fishing rights and food security. But Wu was now telling me that this was, in effect, about power.

My visit to the institute concluded with a tour of a room full of wall-mounted maps, carefully assembled to build the picture of China’s historical control over islands in the region, especially those in the Spratly chain. Once again, I was led by Yang, who stood off in the distance while I gave some of the maps a careful inspection. “Time immemorial” is a favourite official expression for explaining the duration of its claims to them, but as I looked at these old maps, I noticed that despite being written entirely in Chinese, the names of the islands were all phoneticised versions of the names westerners had given them in the 18th and 19th centuries.

* * *

It would be wrong to conclude that the Chinese position merely consists of cosmological bluster, even if it is true that there is plenty of that. Beyond the often glorified and euphemised imperial past, when neighbours reputedly prostrated themselves before the emperor in order to enjoy the privileges of trade, China draws on far fresher sources of motivation. Beijing’s attitudes toward the South China Sea, like much of the country’s behaviour as an emerging superpower, is bound up in an entirely modern Chinese obsession: overcoming the humiliations of the recent past.

Since Sun Yat-sen, the early-20th-century founder of the Republic of China, every modern leader has harboured dreams of restoring the country to the position it enjoyed before imperial China was ripped asunder by Britain (and France) in the opium wars, and then trampled by Japan in a series of degrading wars that began in the 1890s. For Chinese leaders of the 20th, and now 21st century, that means restoring lost territories: most obviously Taiwan but also the Diaoyu islands. Just as important are the rights China is convinced – or has convinced itself – it deserves to the South China Sea.

Sun’s successor, and Mao Zedong’s greatest historical rival, Chiang Kai-shek, began keeping a diary in 1928, in which he created a daily entry under the heading Xuechi, meaning “avenge”, or “wipe clean humiliation”. It came to include everything from venting about the need to destroy the “dwarf pirates”, which is how he often referred to the Japanese he was at war with, to the need to eventually create textbooks that would inculcate his ideas about the people’s duty to restore China’s size and glory. One entry reads: “Recover Taiwan and Korea. Recover the land that was originally part of the Han and Tang dynasty. Then, as descendants of the Yellow Emperor, we will have no shame.”

Nationalism in China, which has swelled around these kinds of sentiments, has become a vital tool for the Communist party leadership. Yet officials have sometimes stoked these feelings in such a crude manner that it has become a hindrance to their freedom of action, and potentially even a threat to their own survival. When the Chinese foreign minister, Wang Yi, said in June, for example, that any retreat by Beijing from its South China Sea claims would not be forgiven by future generations, he might as well have said that the country’s leaders could not get away with compromise on these issues.

But there is an even more recent imperative at work in Beijing’s calculations than the matter of overcoming the humiliations of the last two centuries, and its name is the US. Today, it is that country and not Europe or even Japan, which is seen as the main obstacle to Beijing’s regional ambitions. There is simply no way for China to reign supreme in the South China Sea so long as the US has a free run of the western Pacific. Even more than cowing its neighbours, China’s island-building strategy would seem to have the US navy as its primary focus.

There is no way for China to rule the South China Sea so long as the US has a free run of the western Pacific

The waters off Hainan, near the Yalin navy base, where China maintains its nuclear submarine fleet, are notoriously shallow, scarcely 10 metres deep in many places, making it easy to spot submarines on their sorties from the island. By establishing a number of man-made island positions in the Spratlys, China seems to be pursuing a number of complementary goals. The first is reducing the ability of the US fleet to operate with impunity throughout the region. It is frequently noted that China’s tiny new islets would be impossible to defend in a conflict, but that is to miss the point. By establishing radar and maritime acoustic arrays throughout the South China Sea, along with surveillance flights of its own, Beijing will improve its real-time information, or situational awareness in the region and enhance its ability to engage enemy combatants before they can approach the Chinese mainland. As noted, with its deep surrounding waters, a place such as Fiery Cross might also serve as a convenient way station for China’s submarines.

It may turn out that the encounter with the US Poseidon surveillance aircraft recorded by CNN was more than passingly revealing about China’s ambitions for its newly built islands, and about the geopolitical contest that will unfold around them. Under Unclos, which China signed in 1996, and the US has never ratified, artificial islands built atop submerged features such as the reefs flown over that day do not entitle a country to territorial rights – and yet, there was the presumed voice of a Chinese soldier telling the Americans to go away.

From declaring that it will not abide by any Unclos ruling against it, it would not be such a large step for China to depart from Unclos altogether – particularly since the US has never joined – and insist that its new positions in the South China Sea be given a wide berth by others, in the surrounding waters and in the skies overhead. Such a decision would be risky for China in terms of the image it would like to project as a peaceable and constructive rising power, but challenging it would be risky for others, not least the US.

On the eve of a recent tour of the region, where he attended an annual Asian security conference in Singapore, the US defence secretary Ashton Carter vowed to frustrate any Chinese efforts to limit the movements of American vessels in the South China Sea. “The United States will fly, sail and operate wherever international law allows, as we do all around the world,” Carter declared in Pearl Harbor. And to this, he joined another vow. “We will remain the principal security power in the Asia-Pacific for decades to come,” he said.

Unsurprisingly, in China, people have begun to take a different view of the future. “In 10 years, our GDP will be bigger than the US, in 20 years our military spending will be equal to the US,” said Shen Dingli, one of China’s most prominent international relations scholars, who I met in Washington. “Thirty to 40 years from now, our armed forces will be better than the US. Why would the US defend those rocks? When you have power, the world has to accept. The US is a superpower today, and it can do whatever it wants. When China is a superpower, the world will also have to accept.”

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