High resolution: Eurotecture invades Manhattan.

I’m in a European cultural building. That’s obvious. The little details give it away: the delicate white-painted steelwork, the way the slender handrails are bolted directly into the glass walls of the lifts, the confident juxtaposition of new with old. Were are we? Zurich? London? Neither. Look up and out of this great library and museum, and you see the pinnacle of the Empire State Building. We are, as the Morgan Library’s Italian architect, Renzo Piano, puts it evocatively, “swimming in Manhattan”.

The library – one of the world’s finest collections of rare books, manuscripts and drawings – exists in a jumble of existing historic buildings on Madison Avenue which Piano has juggled with enormous skill. He has used a generous budget of $106m to create a sunlit public concourse at ground level, plus new galleries and a concert hall excavated deep into the bedrock below. It is very good: evidence that Piano is right back on form. Bustling Manhattan is out there, but inside, all is calm in that distinctly Old World, mature-high-tech manner.

He is only one of a jostling crowd of architects from Europe and points east now invading New York, however. Further north on Eighth Avenue up near Columbus Circle, the finishing touches are being put to the first modern skyscraper to be built by an Englishman in New York. The crinkle-crankle latticework of Norman Foster’s 42-storey Hearst Tower rises, like a glittering concertina, from the middle of the existing 1928 Art Deco HQ of the Hearst media empire. It is all but complete: 2,000 “Hearstlings” as the employees are called, have started moving in. This is not just a Brit-designed skyscraper: it is, by New York standards, a flagship low-energy “green” building on the European model: light on steel, heavy on recycled materials. Soon they will turn on the spectacular “Icefall” water cascade in the huge lobby which will climate-control the whole building. Elsewhere is a huge wall painting by Richard Long.

Manhattan’s media seem to have gone overboard for European architecture in the most direct way possible: they don’t just write about it, they build it. Piano’s other big project there is the headquarters tower for the New York Times, now rising fast over the western fringe of the theatre district. While Foster’s Hearst Tower was commissioned shortly before the world-changing events of 9/11, Piano’s New York Times tower was the first to be approved afterwards. It represented a vote of renewed confidence in the Manhattan skyline. With its ceramic-bar façade grillage it again has a relatively delicate level of detailing which is very unlike the brash heritage of skyscrapers in this town. Close up, the Empire State, Chrysler Building and Rockefeller Center are crude indeed. Who cares? That toughness is part of their charm and their main visual impact is from a distance. But the Eurotects do things a little differently. They are more used to designing buildings at fine resolution. That is why the New York products of the last great European modernist invasion in the 1930s – Mies van der Rohe, Marcel Breuer, Walter Gropius et al – still seem slightly alien in this context, even though they helped to define it.

There have been a few problems with the recent influx of overseas big names to design key buildings. The capacious chill corporate lobbies of the new Museum of Modern Art, for instance, were designed by the Japanese architect Yoshio Taniguchi in his customary style of exquisite restraint: sadly the builders were not quite up to Japanese levels of excellence, and the struggle is evident. In contrast, Piano has worked wonders with the Morgan Library. There are very few clunky moments. But then for that budget (much more per square foot than MoMA) you would damn well expect perfection.

There are plenty more Eurotects in town. Down near the World Trade Center on Fulton Street, Sir Nicholas “Eden Project” Grimshaw is combining a maze of existing stations into one ambitious glass-domed transit interchange. In the centre of the site itself, Spain’s Santiago Calatrava is doing a differently glassy station, plus a dizzying apartment tower at South Street on the East River. That will be made of 12 four-storey cubes stacked up on masts. The ever-busy Foster has been signed up to do one of the cluster of new World Trade Center towers. So as night follows day, our other leading architectural Lord, Richard Rogers, Foster’s one-time design partner, is also on the scene. He will be doing a companion tower to Foster’s at the World Trade Center, but he has plenty else on hand, including the job of rebuilding the vast Jacob Javits convention center on Manhattan’s west side. Rogers is also masterplanning a whole chunk of waterfront.

Tramp the sidewalks long enough and you’ll maybe bump into the black-clad, shaven-headed, burly figure of Jean Nouvel, France’s superstar architect, who is getting on nicely with his apartment block up in the SoHO district. The ultra-modish Swiss pair of Jacques Herzog and Pierre de Meuron, who gave us Tate Modern, are doing a hotel-and-apartments complex for the king of high-style hotels, Ian Schrager. Arguably Schrager started this whole European frenzy rolling with his early and enthusiastic espousal of France’s Philippe Starck years back, but he has now grown out of Starck’s Tiggerishly mischievous style. Schrager is also working with British minimalist John Pawson. It seems there is no stopping the march of the Europeans.

Our own Zaha Hadid is getting the honour of an exhibition devoted to her at the Guggenheim Museum, starting next month. Since she is already building elsewhere in the USA, New York projects will surely follow. This follows a big show on contemporary Spanish architecture, staged by MoMA. Put all this together, and you have to ask why. Why is New York, with its heritage of superb architecture, looking across the Atlantic for its next generation of landmarks?

It’s only a leavening – after all, most building in New York will continue to be done by Americans – but such leavenings make all the difference. Two things have changed since, say, the 1990s. The first is that the city’s planning regime has got very keen on European ideas of urbanism and is putting the emphasis on quality. The second is that the all-powerful development lobby in the city, so long mired in stagnation, has become a little starstruck. It now regards design quality as a powerful sales tool. Sheer floorspace, even location, is no longer enough: added design value is now the mantra. The seemingly sophisticated Europeans with their expressive architecture provide the necessary sales impetus. Brazen commercialism has taken a new twist.

And space for new buildings can always be made, even in confined Manhattan. On the west side, a long-derelict elevated goods railway, the “High Line” is going to be turned into a linear park. That is good in itself, but the development that will be unlocked by the High Line as property values around it soar is something else. A mini-boom is pending.

Although things were already starting to change, there is no doubt that the events of 9/11 had a fundamental effect on the way the city sees itself. The soul-searching that followed, the competitions and squabbles over the Ground Zero site, in a way gave the city permission to change. The one name I’ve not mentioned so far is the catalytic one of Daniel Libeskind, who won the competition for the Ground Zero masterplan, moved to New York from Berlin, and then gradually got sidelined. Even the famously self-promoting Libeskind can’t claim credit for all of this. But there’s enough evidence to suggest that, once he’d jammed his foot in the door, everyone else shouldered their way through.

Text, and photos of Hearst tower and Morgan Library, © Hugh Pearman. A fuller version of the article first published in The Sunday Times, London, on May 14, 2006, as “New York’s brave old world”.