Should Britain return the Parthenon marbles?

Breasts and drapes in marble (The Guardian)

Should Britain return the Parthenon ("Elgin") marbles? While promoting his new film Monuments Men, about returning art taken by the Nazis to its rightful owners, George Clooney has said that the UK should give the Parthenon marbles back to Greece. Are you with him? Guardian poll, closes at midnight on Saturday. At the moment there is an overwhelming majority (88%) in favour of returning the fragments but disappointingly there seem to be a lot of British nationalists represented in the comments.