To deter looters, Buddhist priests are now sleeping amidst the ruins of their temples. Something akin to this was done, if memory serves, to try protect Angkor Wat as well. This kind of mobilization of believers in heritage is deeply moving.
It is also of importance that international agencies mobilize, as UNESCO is doing. But one big question that will have to be thought about after the fact is whether the UNESCO fact-finding mission structure is really the best way to deal with these kinds of disasters, or whether it makes more sense to invest the very scarce resources of UNESCO instead in disaster response plans so that even after a catastrophic event like this one there an in-country response team tied in to local volunteer groups is ready to get started assessing and mitigating, with call-back capacity to UNESCO and via UNESCO to the Smithsonian and other cultural heritage protection organizations. No such disaster plan appears to have been in place for Nepal. This despite 2 inscribed sites and 15 more on the tentative list of World Heritage Sites.