Naturally, there will be those who will disagree. After all, what is the promised new gallery but a converted power- station on the banks of the River Thames? Not much great new architecture there, you might think.
Surely, here was a chance to design a new gallery to rival the best work by, say, Richard Meier or Frank Gehry - a gallery to place a full stop at the very end of 20th-century art. And to welcome in the century to come.
What the Tate project does do, however, is to raise the art of English compromise into Art. The conversion of the former Bankside power-station into a giant public gallery devoted to modern art promises to do many things that a brand-new building, no matter how desirable, could never have done.
To begin with, the transformation of temple of power into powerhouse of art is achievable. Nicholas Serota, his trustees and advisors did consider very carefully the possibility of a custom-made building. The problem they faced was one that affects all of us living in British cities. How can there be room for a new building, especially one as ambitious as the new Tate, if every existing building, no matter how good or bad, is treated as an invaluable part of our national heritage? We live at a time when bland Sixties office blocks are being wrapped in intellectual cotton-wool and being treated on a par with the work of those who built our medieval cathedrals.
There were, of course, several empty sites in central London where a bold new building might be erected, but these were either in the wrong place, too expensive, or else scheduled for some other more immediately lucrative purpose.
And so the new Tate had to be a compromise. If you are going to compromise, however, make sure you do it well.
The Herzog-de Meuron scheme is a brilliant compromise. This is not altogether due to the architects. In fact, their design and their part in the complete story is a relatively simple one. They have designed a simple interior, which promises to be spectacular in parts, and have intervened in the aesthetic of Sir Giles Gilbert Scott's power station as little as possible. The brilliance of the compromise lies in the fact that the Tate has been able to commission a firm of architects (foreigners, too; a great rarity in a guarded and suspicious little England) whose work is at what is called the "cutting edge" of their profession. Yet the shock of the new has been intelligently muted by having these Swiss types perform their ministry within the confines of an existing architectural fabric.
This means that the Tate, while boasting what promises to be an ultra- modern interior, will still be good old Bankside power-station on the outside. Actually, the good old power- station was never much loved. Built in the shadow of St Paul's Cathedral, it has always threatened its magnificent baroque neighbour with soot and smoke. Yet, rightly or wrongly, it has won the minds of the powerful conservation lobby. By keeping the powerful profile of Scott's Bankside, the Tate is likely to stay sweet with conservationists.
Serota and his team know that there is legitimate and even great precedent for installing fresh and even controversial interiors into old buildings. Few people who have visited the Castelvecchio in Verona, for example, would decry the subtle interior installed by the charismatic 20th-century Venetian architect Carlo Scarpa; Scarpa made the castle into a beautiful museum and gallery without undermining its historic presence. The same thing will be done at Bankside.
More than this, the new Tate will become, already is becoming, a vital ingredient in the re-creation of Southwark, a borough that for too long has presented a poor and shabby face to the River Thames.
The promise of the Tate (which will draw at least three million visitors a year) has drawn the capital's more adventurous property developers out of the recessionary woodwork. Opulent new flats for the privileged and city slick are on their way here, as well as a big student hostel and any number of plans for restaurants, bars and cafes. The local borough (one of London's poorest) has been generous in encouraging such glamorous development. It has also been wise in encouraging a mix of new uses for old sites and buildings that will continue to allow people on average and low incomes to live cheek-by-jowl with the new gallery.
A new pedestrian footbridge will link Bankside to St Paul's, linking the City of London to Southwark. This will benefit not just tourists (and thus boost traffic through the new Tate), but those who live in Southwark and work in the City. The bridge is very likely to be a jewel-like structure that will enhance this tough stretch of the river.
The Tate links modern foreign architects with both local and national concerns. It balances our obsession with heritage and conservation against the latest design. It puts what might elsewhere be considered "elitist" architecture into a popular context. It changes the nature of art gallery from that of lofty shrine to that of urban generator. It demonstrates that those who commissioned the scheme have grasped the wide historic and urban implications of building on a city centre site. The new Tate is not to be a winking, shining spaceship of a building landed on some sensitive spot and oblivious to native sensibilities and designs. It is more deus ex machina than Modern Movement machine.
All these things will make it used, successful, respected and admired. If it is a compromise, it is one of which Bentham and Mill would have approved: it is the one most likely to please the greatest number.
It will be unlike, for example, such unfortunate design compromises as the ugly National Gallery extension, a wimpish building that musters no sense of occasion, which fails to a spectacular degree to address Trafalgar Square and which makes no use of the potential of a site that had been waiting for something good to happen for 45 years. That is how not to compromise.
Somewhere in Britain, however, we should allow ourselves the chance to build without compromise. While the funding of the Tate project has been a great moment in the story of Britain's architecture this year, there must come a time when we can build again with passion, energy and individuality and stop clinging to the comforts of a past that was, truth known, never as glorious as the future could be.
n Overleaf, Paul Taylor recalls the theatrical 'Moment When' of 1995Reuse content