Melanie McDonagh: The only public space left is the market place

The loss of the landmarks of civic life

Ten minutes down the road from me in west London, there is a fine and distinguished building – so fine and distinguished that it is used for film sets – which now houses the Government's art collection and was originally opened by Edward VII as an educational institute. Next to it is another building in a similar style but smaller scale which also suggests a function of civic importance. It now houses, I believe, a PR company. Until two years ago it was the local post office.

It closed, as did 4,000 others, in 2006. The post office then moved to a branch of Costcutter which, however convenient in terms of opening hours, had little obvious civic dignity. Then a branch of Tesco Express opened next door, and when, as a result, the Costcutter branch closed, that post office shut too. Now the little newsagent-cum-post-office to which residents went instead is to go in the latest round of government-driven closures of 2,500 branches. I now avoid sending parcels and buy stamps at WH Smith or Tesco.

The removal of post-office services from a public building of architectural merit to a till in Tesco is the direction in which many public services are moving. Notwithstanding the move to allow some councils to take over some post offices, institutions whose municipal dignity is reflected in their buildings are being farmed out to any retail outlet that will have them.

The Culture minister, Margaret Hodge, gave a speech to librarians last week in a similar vein – even though it had the saving merit of acknowledging that books were what libraries are meant to be about. But she still invoked the lofty ideal of having libraries in supermarkets – "centre-stage and customer-focused" – and asked which of them would be the first to incorporate a branch of Costa or Starbucks. And she insisted – inevitably – on branches being also Jobcentres. Remember the fuss when the Victoria and Albert Museum advertised itself as an ace restaurant with quite a nice museum attached? Same idea.

My nearest library gives mute testimony to what the Victorians meant by a municipal institution – it is spacious, dignified, and witnesses an engaging reverence for learning, with statues of Shakespeare, Bacon et al on the front. True, subscription libraries opened in branches of Boots from the end of the 19th century, but the main public libraries were given architectural importance because they had real municipal importance.

Then there is the Victorians' other gift – public lavatories. Yet they have been in steady decline – according to the British Toilet Association, 5,000 public loos closed in the past decade. Last week, there was an initiative launched by the Communities Secretary, Hazel Blears, to "take the taboo out of toilets" by encouraging pubs to allow people to use their loos. We've come a long way from the Victorian architectural competitions to commission the finest public lavatories.

There is a common thread to the downgrading of libraries, post offices and loos – and it is a steadily decreasing respect for public institutions. Ruskin, that eminent Victorian, felt that public buildings ought to be beautiful and dignified because he had an elevated conception of what our common civic life is about. It is something our political establishment doesn't begin to understand.