One commenter makes an extremely cogent point in the other direction. After pointing out the importance of outside help to relieve exhausted local S&R, this ethical plea:
There is also an emotional necessity to bringing in more S&R, even when other types of aide are desperately needed. How well could other aide workers function, if they knew that people were trapped, local rescuers exhausted to collapse, and no one is left to do the last of the “digging out”? For both local and foreign aide workers, the decision to leave trapped people to die so that the effort can be made to help in other ways would be a difficult one. Knowing that the S&R is continuing eliminates that distraction.I wonder for how many other disease or development related projects this is also the case? I can focus on hunger, comforted that someone else is handling malaria, who is in turn comforted by knowing I'm trying to get them fed. Is this a positive externality? Are different interventions complementary? Would you dare propose a study that could experimentally demonstrate it?