Throughout history, mighty conquerors and hungry peasants alike have plundered palaces, tombs and museums, carrying off priceless artefacts. Some are melted down, some go to prestigious museums, some vanish into the chaos of combat and some end up in the secret hoards of the unscrupulous rich.
The Middle East and North Africa in particular have lost countless antiquities, from Babylon's enormous Ishtar Gate - parts of it are in museums in at least six countries - to countless tiny artefacts smuggled away individually or wholesale. Just this week, The National reported that items looted during Libya's civil war have turned up at Christie's auction house, which duly alerted authorities.
The old regimes of the Arab uprising states, for all their faults, often protected museums and other patrimonial assets. But civil war, lawlessness and fundamentalism have seen antiquities looted, in a continuing slow-motion tragedy: reports this month tell of Syrian rebels at the Lebanese border, trading artefacts taken from museums for weapons.
In September, the burning of Aleppo's medieval souq was yet another tragedy for Syria; last year, the destruction of the Egyptian Scientific Institute saw tens of thousands of historical documents destroyed.
Well-intentioned outsiders can do little to prevent such events. They can, however, help to stop the haemorrhage of artefacts. So can governments, by strongly supporting anti-smuggling efforts.
Many countries deem newly discovered antiquities to be state property. Even a medium-term view of history shows that states can be fleeting, but there is surely a broader interest in keeping items from Arab history, for example, in Arab hands. Regional cooperation, including monitoring of international dealers, could help.
There is also the more symbolic, but less urgent problem of recovering artefacts once looted but now housed in reputable museums. Egypt, for example, has long wanted Germany to return the 3,350-year-old bust of Nefertiti discovered and claimed in 1912 by German archaeologists. Egypt has first claim to it own antiquities - so long as it can place them in secure exhibitions.
In the latest case, Christie's did exactly as it should, as would be expected of a respected auction house. The worry is for those artefacts that fall into less reputable hands.