In the UK there is a row growing about the return to Greece of the Elgin Marbles . These were originally in the world famous Parthenon.
In my view these should be returned.
Although I stand to be corrected, these were essentially stolen! My suggestion is a copy of these should be made and displayed (this has been done before e.g. the Alfred Jewel in the Ashmolian Museum in Oxford). Their proper home is in the Parthenon in Athens, which is visited by millions.