Leading article: The true value of our creative industries

As he seeks to define his political legacy before the clock runs down on his Premiership, Tony Blair turns his attention today to the arts. The Prime Minister will thank an audience of eminent figures from the British cultural establishment for pulling off a "quiet revolution" in our artistic life during his time in office. If this revolution has indeed been "quiet", Mr Blair must accept some of the blame. The Prime Minister has spoken far too infrequently about the arts over the years. This has given the unfortunate impression that culture is relatively unimportant.

But, on the whole, this Government has a very respectable record of promoting the arts. Life has certainly been better for Britain's great cultural institutions than it was during the dark days of the Thatcher and Major administrations. Despite deep antipathy to Mr Blair personally among the art world, mainly because of the Iraq war, the sector has prospered under New Labour. The Arts Council's budget has risen from £186m in 1997 to £412m today.

The introduction of free national museum access has almost doubled visitor numbers. The contemporary art scene is flourishing, as demonstrated by the soaring popularity of the Frieze Art Fair and Tate Modern. The performing arts have done well, too. Theatre audiences have risen by about 8 per cent and the British film industry, despite some output that is best left unmentioned, is showing some signs of recovery.

The cultural boom is by no means restricted to the capital. Regional theatre is thriving. Liverpool is preparing to become the European City of Culture next year. And inspiring public sculpture has sprung up across the country in the past decade, from Antony Gormley's Angel of the North on Tyneside, to Maggi Hambling's scallop shell memorial in Suffolk. Not all of this artistic activity can be attributed to the Government, of course. But New Labour has certainly created the conditions in which the arts have been able to flourish. For that it deserves credit.

Yet there is something unfortunate about the timing of this speech. It comes as a series of considerably tighter Treasury spending rounds loom on the horizon. Arts Council England has already been told that its budget will be frozen in 2008. And the feeling is that the arts will be the first to be squeezed in future. The British Library has already raised the spectre that it may be forced to charge for access to its reading rooms. Compounding this sense of insecurity are fears that the spiralling costs of the 2012 London Olympics will siphon off the public funds available to the arts.

The Government's responsibilities are clear. It must keep to its side of the bargain over free museum admission. Sustained high numbers of visitors mean institutions need sustained high funding to cope with them. The Government must also recognise that arts organisations need funding that allows them to thrive, not merely to eke out an existence.

Ministers should bear in mind that art spending is a good national investment. The number of tourists visiting the UK bounced back last year, after a poor 2005. And seven of the top national visitor attractions were publicly funded museums. In 2002, it is estimated that Britain exported cultural goods to the value of £5bn. The creative industries are growing faster than any other part of the economy.

But this is about something far more significant than money. Mr Blair - and his likely successor, Gordon Brown - must demonstrate that the arts are not merely some desirable, but essentially optional, aspect of modern Britain. Both must make it clear that the arts constitute the very life-blood of a civilised nation.