That's ours. No, it's not. Who really owns culture? Keep them here (3 of 3)

he move to return the Elgin Marbles to Athens casts Lord Elgin as an imperialistic vandal when he, in fact, performed a supreme act of cultural rescue. Taken to its logical conclusion, the restitution campaign endangers the whole concept of a cosmopolitan museum by threatening to trigger an artistic version of ethnic cleansing in which every cultural artefact would have to return to its geographical roots.

The late Melina Mercouri, when she was Greek Minister of Culture, presented the Parthenon as "the most precious symbol of our nationhood". But when Lord Elgin's team of scholars and artists arrived in Athens in 1800, many of its carvings had been lost and others had been defaced by both Greeks and Turks. Only four figures survived on the west pediment - two of which had lost their heads. Fifty years earlier, there had been 12 figures. A hundred and twenty-five years earlier, there had been 20.

In this century, under Greek stewardship, severe pollution and bungled restoration have added greatly to earlier injuries - a fact that mortifies and offends Greek scholars no less than their British colleagues. Professor Charalambos Bouras of Athens University, a member of the Committee for the Conservation of the Acropolis Monuments, has said that 20th-century restorations on the Acropolis have been "a terrible disaster" with effects that were "truly catastrophic for the monuments" including "numerous fractures, ruptured members and grotesquely discoloured stone surfaces".

Even as the surfaces of marbles in Athens are flaking off and "crumbling like sugar at the touch of a hand", the restitutionists flog the British Museum. They complain of the unauthorised use - which was halted - of soft copper chisels during a cleaning in the 1930s but not about the authorised use of much harder steel chisels and wire brushes in Athens during the 1950s. They were used to strip patina from an entire frieze of carvings on the Parthenon's sister temple, the Hephaesteion, leaving stones as bare and as white "as the day they were carved".

Miss Mercouri was careful to present the Elgin Marbles as "an integral part" of the Acropolis (the site of the Parthenon) and not of the Parthenon building itself from which they were removed. Her political nous is not shared by Christopher Hitchens who rails against what he characterises as Elgin's act of "amputation of sculpture from a temple" - an act which, he insists, "would be execrated if committed today". It is, in fact, being committed today without execration on the Parthenon itself in the name of conservation, as sanctioned by Article Eight of the 1964 Charter of Venice.

The difference is that where the Marbles removed by Elgin were structurally sound, those being taken down now are greatly corroded and weakened, often needing to be stored in nitrogen-filled glass cases. It would not be possible to reintegrate the Marbles with the Parthenon, as Miss Mercouri realised. Nor would it even be possible to reintegrate them with the Acropolis.

A museum that could rehouse all of the surviving Parthenon marbles would have to be bigger than the Parthenon itself. A plan to build such a museum at the foot of the Acropolis has been rejected by Greek archaeologists because of the importance of the site, and by architects because of the vulgarity of its design.

What then are we to make of the restitutionists' mantra that the Elgin Marbles make no sense when seen "out of context" in London? Their original context in Athens no longer exists and cannot be replicated. The Acropolis today is an artificial 20th-century construct made by a brutal sweeping away of all historical evidence of Christian and Muslim usage of the site.

The truth is that, as even Lord Byron (the first British restitutionist) could see, the Elgin Marbles as works of art look every bit as "poetical" in London as in Athens. Currently, they are seen for free by some some six million visitors a year, within the context of artefacts drawn from other cultures and other periods.

The restitutionists' desire to thwart such extraordinarily rich and rewarding encounters is narrowly parochial and technically philistine. It rests on the notion that art - even supremely transcendent classical Greek art - belongs only to the soil from which it sprang. We would rightly recoil if the Germans were to revive such Wagnerian nationalist sentiments. We do the modern Greeks no favours by enabling their politicians to divert attention from the crisis that exists today in the management of Greek heritage sites which are being effectively destroyed by unchecked tourism, commercial over-development and pollution.

It would be best for art if everyone who cared for antiquities were to unite in a campaign to improve conservation policies throughout the world rather than waste their energies fighting and refighting a pointless war over the removal of carvings from Athens to London two centuries ago.

Michael Daley is an artist and director of ArtWatch UK, the lobby group that campaigns against bad restoration work.