I think that's a good thing, you wouldn't want to put them back until after the bombing has stopped -- they could be broken. The safest place for them now is right where they are. When the earth stops rumbling and the dust is swept up and the museums are open again -- then we can put them back for the nice Iranians to appreciate. There, there, now.
Aren't these the guys who are smashing and obliterating all local artifacts that aren't muslem-ish?
:') If the artifacts were looted after the international ban on laissez' faire antiquities trading (as opposed to what went on during the European colonial period), they should go back. One problem of late has been that unsubstantiated claims that pieces came from looting has been recognized as legal claims.