However much lip-service politicians pay to the importance of art, they stop pretending at election time. Amid the avalanche of promises about tax, pensions, hospitals, crime and schools, references to galleries or museums become desperately hard to find. Convinced there are no votes in such airy-fairy matters, political leaders on the campaign trail quickly forget that art exists.
They must be hugely relieved to do so. After all, their knowledge of artists is negligible, and they never bother to attend major exhibition openings. I was astonished, one morning last year, to come across Boris Johnson at Tate Britain. With a grumpy expression, he was wandering around the new Tracey Emin room accompanied by some television people. They introduced us, and Johnson informed me with mock amazement that he had just been appointed shadow arts minister. He made a dismissive comment about Emin. I challenged him, and was intrigued to watch him jotting down a note of my remarks in a little pocketbook. But I never discovered why: within days of our bizarre encounter, he had been summarily dismissed from his new post.
Johnson's scorn for Emin was predictable enough. Most Tories loathe provocative contemporary art so much that they would like, ideally, to slash its public subsidy. That's why I was so surprised that Johnson was willing to talk to an art critic. Politicians of all kinds normally do not listen to people like me. Most of the time, they leave that kind of thing to the Arts Council. And they are probably delighted that most of the brickbats are aimed not at them, but at the council's chairman, Christopher Frayling, and his staff.
With tedious regularity, journalists angrily call for the Arts Council's abolition. But they fail to realise that the alternative is far less accountable. Senior civil servants, if they were given the job of subsidising art, would be adept at evading public scrutiny. Nobody would know whom to attack any more, whereas Frayling is sufficiently tough to argue his case in full-length newspaper articles. He is prepared to be a target, and, in that respect, the Arts Council is more democratic than any governmental alternative.
What we need from our political leaders, now that their wearisome election verbiage has died down, is a genuine sense of vision. They ought to develop an authentic belief in art, and sincerely proclaim their determination to ensure that it thrives. Labour deserves credit for putting the principle of free museum admission into practice. After years of bewildering Tory machinations, when some national collections charged entry fees while others refused, turnstiles were abolished. The public has responded by visiting these liberated institutions in great quantities.
Labour then lost its way, becoming obsessed by statistics about attendance. The fundamental reason people should be encouraged to encounter art was forgotten. Politicians seemed bent on the importance of crowds passing through our museums without lingering long enough to scrutinise the images on display. Outstanding works of art deserve more than a token glance. They repay prolonged exploration. But the millions who fill Tate Modern often seem in too much of a hurry. Perhaps they are conscious of what else remains to be viewed in this immense, overwhelming powerhouse. The sheer vastness makes them feel perpetually anxious to move on, rather than pause and allow particular works to disclose their full meaning.
I am increasingly convinced that we should concentrate, now, on this act of visual discovery. There is no point in cramming public galleries with ever greater numbers of people if they do not learn how to look. We need to apply a searching gaze, and the government must do far more to help our national collections achieve this goal. At the moment, their directors' energies are too often caught up in the struggle to find money. Very recently, Charles Saumarez Smith of the National Gallery complained that its government grant was wholly inadequate for acquiring top-flight works. Every time an exceptional painting is offered to the gallery, a protracted and exhausting campaign must be waged to obtain funds from a bewildering range of sources. Government cash plays only a parsimonious role in such Herculean battles, and Britain lacks the abundance of wealthy patrons who have made such an indispensable contribution to great public collections across the US.
A couple of weeks ago, the Museum of Modern Art in New York proudly announced that David Rockefeller had pledged to it a $100m endowment - the largest monetary gift in MoMA's history. Rockefeller's mother co-founded the museum in 1929, so she and her son have been instrumental in creating the world's finest collection of 20th-century art. David, along with his late wife, Peggy, has either given or promised MoMA an array of masterpieces by Cezanne, Derain, Gauguin, Matisse and Picasso - precisely the kinds of works that the National Gallery, not to mention Tate Modern, would love to acquire. Yet the stratospheric prices commanded by such paintings lie far beyond the reach of our public collections. And no British benefactor is ever likely to give them pictures of this standard.
The most remarkable donors in this country are people from abroad: Anglo- phile members of the Getty family or, more recently, wealthy Middle Eastern philanthropists. Next year in London, the Jameel Gallery of Islamic Art will open at the Victoria and Albert Museum, funded by a £5.4m gift from the Jameel family. It will enable the V&A to display one of the most resplendent collections of Islamic art. Meanwhile, the Ashmolean Museum in Oxford has just announced a £2m donation from HRH Prince Sultan bin Abdul-Aziz al-Saud, Saudi Arabia's second deputy minister and minister of defence and aviation. It will help to create a home for the Ashmolean's celebrated Islamic collection. And before long, London will be the recipient of an entirely new gallery, funded by the Iranian-born collector Professor Nasser Khalili. He wants to erect and endow a building, on a central site, for his vast personal collection of Islamic art.
Such initiatives are long overdue, and should do much to foster an enlightened understanding of Muslim culture in Britain. Beguiled by such Middle Eastern munificence, the government can easily persuade itself that our museums need no extra help from the public purse. Outside the charmed circle of Islamic lar-gesse, however, the needs are great. Take the Imperial War Museum where, due to chronic lack of space, important paintings by Stanley Spencer, Paul Nash and Wyndham Lewis are hidden in storerooms.
Politicians could do far more to adjust the tax laws in order to encourage our exceedingly prosperous citizens to follow the Rockefeller example. But their wealth should not just be directed at metropolitan institutions. Our culture is unhealthily London-centred, and even cities as substantial as Birmingham and Leeds require urgent help to boost their woefully under-nourished municipal galleries.
Our political leaders should realise, too, that art can thrive beyond the boundaries of the museum. In New York this February, Central Park was transformed for 16 days when Christo and Jeanne-Claude persuaded the city's mayor, Michael R Bloomberg, that 7,500 freestanding gates could be installed in this epic open space. Gold-coloured fabric panels were suspended from their frames, free to move in the wind, emblazoning the 23 miles of walkway with sumptuous, festive colour. Whether seen from below as an ever-shifting golden ceiling, or from distant buildings, where it resembled a great glowing river, The Gates provided countless spectators with a revelatory, democratic and, above all, joyful sense of wonder.
Why can't similar settings in Britain be enlivened by temporary artworks with comparable audacity? We are so inexperienced at commissioning such ventures that the government ends up funding something as lamentable as the hapless Diana Memorial in Kensington Gardens. Dogged by disasters since opening, the ill-fated fountain is a symbol of our politicians' failure to support modern art in an adventurous spirit. As a judge on the panel for the Diana Memorial, I experienced its intense frustrations at first hand. My vote went to the runner-up Anish Kapoor and his proposal for a shimmering coloured water sculpture. Artists of Kapoor's calibre should be encouraged to transform outdoor settings, and politicians must find out how art's prodigious energies can best be unleashed throughout the nation.
Four paperbacks of Richard Cork's writings on modern art, 1970-2000, are published by Yale University Press