IMHO, the proper way for the British Museum to move forward would be to take the stance that repatriation of these looted artifacts is the explicit policy, and to define the process and necessary steps that need to happen for repatriation, be it the Rosetta Stone, the Elgin Marbles, the Benin Bronzes, etc. Repatriation should be a question of when, not if.

Unfortunately, I get the feeling that the British Museum doesn't have the same viewpoint--returning these looted artifacts would deprive them of their most valuable visitor draws, so they resort to any argument that will let them avoid repatriation. That viewpoint I very definitely do not agree with, and I do not condone in the slightest.