The new programme for the English National Opera has just plopped onto my door mat, and a very satisfying line-up it is. Two operas by Handel (only 10 years ago, you would be lucky to find one), Wagner's great ode to sexual ecstasy in Tristan and Isolde (are love and death really the same?), a new production of Berlioz's mammoth Trojans, plus a round-up of the usual suspects from the Barber of Seville to Tosca and Rigoletto.

It's not until you get to the end that you notice in the small print that this will be last programme before closure for the refurbishment of its home at the Coliseum. No mention of the reports that the closure will be much longer than originally envisaged, nor that the chairman of the board is planning to re-open without a permanent orchestra, on a programme limited to well-tried classics. In other words a root-and-branch change from the opera company we know and many of us love.

The same is true of the Royal Shakespeare Company. After several decades as a mailing list member, I get a short letter to say that a new artistic director has been chosen and a meagre programme of a single London showing in the West End. Nothing is said of the circumstances under which the old artistic director, Adrian Noble, departed nor what is left of his plans. Is the company still going to knock down the Memorial Theatre? Is it to continue to forgo a regular London home in favour of irregular visits? Will it proceed with Noble's intention to break up the old repertory company and replace it with ad hoc touring groups with guest artists?

Quite aside from the wisdom of treating your core mailing customers who book early and book often with such casual contempt – and no US performing company would treat its regulars this way – there is the enormity of what is actually being threatened.

We are talking here not just of two venerable but tired institutions, but the two companies that have done more than any other to make the performing arts exciting and distinguished. Of course the National Theatre and the Royal Opera House are there. But they are both "classic" theatres in that their basic jobs are to perform the regular repertory to high standard.

The ENO and RSC are different. Their role has been to extend frontiers, to be cutting edge. That is the reason they need subsidy. Ticket sales coupled with private sponsorship cannot cope with the risk, artistic and commercial, that such expensive art needs.

And both companies, to those of us who have followed them, have achieved their task with remarkable success. They have had their bad patches as well as their good. That is the way of the arts. But when you think of what the RSC had done over the years – the history plays, the productions of Peter Brook, the chamber plays of Trevor Nunn, the revival of the Jacobean canon – all one can do is gawp in gratitude. And when you consider what the ENO has done – the quality of its chorus, the daring of its repertoire, its 20th-century season a decade ago, Jonathan Miller's mafia version of Rigoletto, the revival of Soldaten, the full panoply of Prokoviev's War and Peace – few companies in Europe have done as well. And none could do it without subsidy.

Which is what is most worrying about the current attempts to change them. What is being proposed is that both cease to be repertory theatres, based on a core of permanent acting and production staff with shared values and a vision. Instead they are to the equivalent of commissioning centres, bringing together forces as and when they need them. And this is not in the name of art but good financial housekeeping.

Which is what it is all about. Under the chairmanship of Geoffrey Robinson and the direction of the Department of Culture, the Arts Council has set its course on producing good housekeeping in the arts, reducing the losses of the big spenders such as the RSC and ENO and getting the subsidised arts ship-shape. It's not interested in what the companies it supports are contributing, just in keeping them on an even keel. And it is actively promoting like-minded businessmen to their boards.

In the case of the RSC we have Lord Alexander, a former chairman off NatWest, who has sailed through the current crisis on the old British tradition that the "higher you are, the less you take responsibility for what goes wrong". And he has been backed by a board that represents academia and actors but none of the customers. In the case of the ENO, the Arts Council and its music director, Hilary Boulding, have promoted an even less inspiring board headed by a city figure, Martin Smith, who seems to want to turn it into a version of his previous musical charge, the Orchestra of the Age of Enlightenment – a perfectly respectable period-instrument orchestra largely supported by corporate sponsors who see it as an uncontentious prestige project at which they can entertain clients.

But then maybe that is the expression of our age. The philistinism of our times, and New Labour's, is not that the performing arts are rejected or even despised, it is that they are seen as a form of background entertainment – the kind of thing a society ought to keep up but not anything that needs to be taken notice of, and certainly not something that should surprise, discomfort, inspire, let alone challenge.

In which case, why should the poor taxpayer pay for it?

a.hamilton@independent.co.uk