‘We have the confidence and ambition,” announced China’s president, Xi Jinping, to a rapt audience last September, “to forge ahead. The strong pass of the enemy is like a wall of iron, yet with firm strides we are conquering its summit. China can do it!” Patriotic, martial words, fitting for a march-past of tanks and missile launchers. They were, though, spoken at the opening of the vast, all-new civilian airport, Beijing Daxing, the most spectacular yet of a building type that keeps getting bigger and grander.

Flying, of course, is an energy-intensive, highly polluting form of travel. One person’s return flight from London to Edinburgh generates more carbon emissions than an average Somalian or Ugandan produces in a whole year. In Sweden, far away from Beijing, the term flygskam, or “flight-shame”, has been coined. It comes with a campaign to encourage people not to fly. In the world’s large and fast-growing economies, however, there is no sign that political leaders are paying any attention. National pride, as well as the convenience and prosperity of their citizens, is at stake.

In April, the first phase of the new Istanbul airport, which is planned when complete to be the busiest in the world, became fully operational. “This is not just an airport,” said the posters that announced it, “it’s a monument to victory.” Changi in Singapore, which has long striven to enthral and entertain its users, outdid itself with its new “Jewel” extension to its existing terminals, essentially a shopping mall and nature-based theme park. From a great oculus in its glass roof descends the “rain vortex”, a funnel of falling water described as the “world’s tallest indoor waterfall”. It has a “butterfly garden”. It has the Shiseido Forest Valley, a 900-tree, 60,000-shrub indoor landscape named after the Japanese-based personal care company Shiseido. The forest concept is, in marketing terms, a good fit with its corporate mission: “Beauty innovations for a better world.”

There have been large and dramatic airports before, many of them in the hi-tech tradition of Norman Foster and like-minded architects: Renzo Piano at Kansai in Osaka, Richard Rogers and his partners at Heathrow terminal 5 and in Madrid, Foster in Hong Kong and at Beijing Capital airport. (The latter, huge and barely a decade old, was rapidly deemed insufficient to meet demand, which is why Daxing was built.) Most adopt an approach pioneered at Foster’s Stansted in the 1980s, that of the uncluttered, elegant roof soaring over the huddled masses grinding their way through the machinery of check-in, security and duty-free. But, however spectacular they might be, they remain rooted in the idea of modernist architecture that the beauty of a building should come from its structure – those roofs are conceived as poems to engineering. The difference now is that sensation and artifice have overtaken the appearance of functionality. These are buildings that want to put on a show.

In Daxing, the late Zaha Hadid was selected, despite little previous experience of designing airports, to work the magic she had previously shown in Galaxy Soho, a curvaceous retail and office development in Beijing. In what turned out to be one of her last projects, she and her office created a great white world of abstracted biomorphs, whose columns and vaults might be the fronds and pads of subaquatic plants or the tendrils of sea creatures. Istanbul’s new airport, designed by the London-based architects Grimshaw, claims to draw on “the architectural character of Istanbul, a city rich with colour, pattern and history since its Byzantine origins”. Jewel Changi airport is designed by the Israeli-Canadian architect Moshe Safdie and his office, who created Singapore’s Marina Bay Sands casino hotel, famous for a 150-metre infinity pool within a 340-metre-long “sky park” perched 57 storeys in the air.

Facebook Twitter Pinterest Beijing Daxing was built in less than five years at a cost of $17bn. Photograph: Ng Han Guan/AP

Similar tendencies can be found at a smaller scale, with an airport that Foster + Partners are designing to serve the Red Sea Project in Saudi Arabia, the self-described “world’s most ambitious luxury tourism development”. Here, say the architects, the airport will be “an integral part of the visitor experience” with an “oasis landscape” running through it. The design is “inspired by the colours and textures of the desert”, its roofs shaped like dunes. “We have moved away from the traditional air-conditioned air bridges that connect the planes,” Fosters tell me, “and opted for an arrival experience through lush landscaped gardens.”

Such airports seek to be more than large pieces of transport equipment. They aim to make air travel an immersive experience as much as a function, a mall or theme park as much as infrastructure. If airports and aeroplanes are usually denatured, with their canned air, their artificial light and their layers of synthetic materials between you and the outside, these models offer you a kind of hyper-nature, confections of foliage and water that you would never quite find in the wild. They offer a new version of the sublime: the scale of Daxing, says Cristiano Ceccato, who led the team at Zaha Hadid Architects who designed it, is like that of the Grand Canyon. It cannot at first be comprehended. It slowly dawns on you.

The Jewel is conceived as a destination in its own right, a place to visit even if you are not catching a flight. “We have people coming here to study,” a senior Changi executive told CNN. “We have people coming here on dates. In fact, we always get requests from residents who want to take wedding photos.”

It is sometimes pointed out that a modern airport occupies the ground area of a traditional city and has a comparable daytime population. With its shops and parks, and its settings for romance and afternoons out, Changi is taking on more of the functions of a city, too.

The wave of airport building is partly a function of demand, especially in the fastest-growing economies of the world. The annual number of air passengers in China has increased from 230 million in 2009 to 611 million in 2018 and is projected to reach 3.5 billion in 2040. Global passenger traffic is expected to double, to 17bn a year, by 2035. These are figures to take your breath and water your eyes. However vast and dominating might seem the current aviation industry and its infrastructure, they will get vaster yet.

Airports compete with each other. Hubs such as Singapore and Hong Kong vie for long-haul stopover passengers who might as well be in one place or another – the one with the nicer waterfall or the shortest walking distances might be the determining factor. They want to lead the annual lists of top airports run by, for example, the consultancy Skytrax (awards that Changi has a habit of winning). They are businesses that want to maximise their assets. If retail makes them rich, and if they have the transport facilities to bring millions to their doors, why not add malls to their terminals?

But the most lavish airports are not pure creations of the market. They are prestige projects, symbols of national pride particularly beloved of the strongman leaders now in power in many major countries, such as Xi, Recep Tayyip Erdoğan in Turkey and Crown Prince Mohammed Bin Salman in Saudi Arabia. Hence Xi’s speech at the opening of Daxing and an earlier visit when the airport was under construction. The new Istanbul airport is the most conspicuous item of the huge portfolio of development and infrastructure (which also includes the third bridge over the Bosphorus and a 30-mile marine canal) with which Erdoğan has tried to boost both his image and the Turkish economy. The planned Red Sea resort is a pet project of the Saudi crown prince.

Daxing and Istanbul were timed to open on politically significant dates, the 70th anniversary of the founding of the People’s Republic of China and the 95th anniversary of the proclamation of the Turkish republic, which in the Turkish case led to the airport being opened before it was really finished. “Look how far we’ve come from being a bunch of peasants,” is, according to Cristiano Ceccato, the message, “from the Long March, from people dying in the snow.”

It is therefore neither coincidental nor insignificant that the airport lies on what Ceccato calls “the national axis of China”, a line heading south from the throne room of the Forbidden City, through Tiananmen gate and down the middle of the roughly symmetrical street plan of Beijing until it reaches the also symmetrical star-shaped airport. “It is incredibly symbolic to them,” he says, “this is now the first gate of Beijing.”

It has been customary for decades for international airports to make more-or-less hokey references to local traditions, the architectural equivalent of the rock star saying: “I love you Stockholm!” The Hajj terminal in Jeddah, completed in 1981 to the designs of the American practice SOM, takes the form of multiple desert tents. The control tower in Istanbul is in the shape of a tulip, Turkey’s national flower. The Western Sydney airport, also designed by Zaha Hadid Architects, will include “aboriginal cultural elements.” Daxing, among other things, is said to take the form of a phoenix, engaged in a conceptual but cosmologically significant dance with Fosters’ dragon-shaped terminal at Beijing Capital airport, which is to the north of the city.

Facebook Twitter Pinterest Beijing Daxing is expected to be the world’s busiest airport with more than 72 million passengers a year. Photograph: STR/AFP/Getty Images

But there’s not much doubting the Chineseness of Daxing – the speed of its construction, for example, (less than five years from official approval to its opening) or its scale. The main building at Heathrow’s terminal 5 could fit twice into the central core of Daxing. You could say that the sinuous Hadid style, although not placeable to any one region of the world, has a non-western quality that suits the new world economic order of which Daxing is an expression. The airport is also Chinese in its combination of mass labour and new technology. It took huge gangs of builders, sometimes using hazardous, old-school welding techniques, to put up a complex superstructure that was aligned by lasers and verified by computers.

The airport serves what Ceccato calls “a growing entrepreneurial class in China, a very autonomous layer of society very adept at doing business”. They fly a lot. They embrace the digital. And so, in addition to the conventional departure and arrivals levels is a third, located between them, for “self-processing”. Here, once users have registered and had their faces scanned, all further security and ticketing checks are performed seamlessly with facial recognition. If you’re untroubled by this level of control – and what else might you expect in an airport but surveillance? – the system is quick and easy.

For Ceccato, the modern airport is an essential component, a “portal” of a new world of mega-cities. “It is not so much that you live in this country or that country,” he says, “but you live in giant urban continuum that is stitched together by air travel.” An airport is creating a time-warp – “if you know how to fly, how to sleep on a plane, you can suddenly be teleported between two points. You’re folding space-time.” He is in awe of the Chinese ability to realise projects like this – “people will call it a dictatorship or a command society but they do get things done” – which he compares with the slowness and expense of building a third runway at Heathrow: “I find that befuddling and quite tragic in a way.”

Infrastructure planning by strongman leaders doesn’t, in fact, always go smoothly. Whereas Daxing is integrated with a large rail and road facilities, the new Istanbul airport is awaiting its metro connections. The design of Daxing, with multiple levels in its centre and a radiating plan, keeps walking distances to gates under 10 minutes; there have been numerous complaints at Istanbul of walks of 20 minutes and more.

It comes with severe human and environmental costs. There were at least 27 deaths in the construction of Istanbul airport, with the pressure of time cited as a contributory factor. Hundreds of thousands, possibly millions, of trees have been cut down and ecologically rich wetlands destroyed. All for an enterprise whose economic rationale – its projections for passenger numbers, its burden on the national debt, at a time when Turkey is struggling to emerge from recession – has been questioned. “The maths just doesn’t add up,” the economist Bahadır Özgür told the Guardian. “This airport is a perfect symbol of modern Turkey.”

Air travel is at once exciting and boring. It rearranges expectations of daylight, meal times and personal space

Ah yes, the environment. Air travel accounts for about 2.5% of global carbon emissions, which, if it may not sound hugely significant, will become more so if passenger numbers double. Frequent flying, in affluent countries, is often the greatest single contributor to an individual’s output of greenhouse gases.

Debate has broken out in the architectural profession following the publication last summer of Architects Declare, a call for action on “the twin crises of climate breakdown and biodiversity loss”. It was rapidly pointed out that the signatories included Zaha Hadid Architects, Foster + Partners and Grimshaw, all of them designers of major airports. Jeremy Till, head of Central St Martins school of art and design called their position “a farce.” “You can’t have a carbon-neutral airport,” he said. Elrond Burrell, a founding signatory of Architects Declare in New Zealand, told the Architects’ Journal that the profession needs to “show moral leadership in the climate emergency: imagine the headline ‘Foster turns down a major airport commission.’”

Almost all major airports now come with claims of sustainable design, of harvesting rainwater, for example, or collecting solar energy. Western Sydney airport, say the architects, will incorporate “sustainable design principles across the building’s architecture as well as its construction principles… The project integrates the extensive use of daylight, natural ventilation and water recycling to create a modular, energy-efficient design.”

For Fosters, air travel is desirable: it “enables people to forge cultural connections, grow their businesses and see the world”. They add that “most sustainable climate scenarios accepted by the UN acknowledge that the aviation industry must grow over the coming years”. New technologies, they say, will eventually reduce the emissions and consumption of aeroplanes. Meanwhile, the best thing an architect can do is to “take the lead to design the sustainable airports of the future”. It is beyond architects’ power to redesign international travel, goes the argument, so they should apply their skills where they can to the structures that serve it.

It is unlikely that the concerns of western architects will have an impact on the growth of Chinese air travel, driven by a newly prosperous generation who, in many cases, are flying for the first time. The concept of flygskam will, hopefully, get established flyers to ask if their flights are really necessary and to find alternative means – a video conference, a train journey – where they can. One might hope that, leading by example, they might offer a version of the good life to be followed around the world, based on the realisation that air travel, with or without fountains and biomorphic architecture, is not actually that pleasant. The much greater likelihood is that the current expansion will carry on regardless.

So there will be more Daxings and Changis, possibly bigger, probably more lavish. Their users will be grateful for their convenience and for the freedoms they give them. They might marvel at the oases and the curvy architecture. They won’t much mind feeding their faces into the airport computers, if it smooths their passage. If the building also serves as authoritarian propaganda, they may not notice.

Air travel creates a strange version of reality. It is anaesthetising and anxious at once, exciting and boring. It rearranges your expectations of daylight, meal times, mobility and personal space. It elides some differences – between countries, for example – and heightens others, such as the divide between those who do and don’t fly. The new breed of airports take that altered reality and alter it some more, to create their own version of the world.

If you want to be dystopian, airports are prototypes for sinister societies of the future, products of the military-entertainment complex where dictatorial government colludes with big business to create controlling environments. Where individuals are pacified by distractions and ruled by technology. If cities and airports really do become identical, that would indeed be scary. Or you could choose to trust that important distinctions will be maintained, contemplate the splendour of the modern airport and enjoy the waterfalls.