Does temporary migration from rich to poor countries cause commitment to development?

Nevermind that none of the journals I've sent it to so far are interested, my new working paper got picked up by Marginal Revolution the king of economics blogs, which is probably way better anyway right?

Public support in rich countries for global development is critical for sustaining effective government and individual action. But the causes of public support are not well understood. Temporary migration to developing countries might play a role in generating individual commitment to development, but finding exogenous variation in travel with which to identify causal effects is rare. In this paper I address this question using a natural experiment – the assignment of Mormon missionaries to two year missions in different world regions – and test whether the attitudes and activities of returned missionaries differ. Data comes from a unique survey gathered on Facebook. Missionaries assigned to treat regions (Africa, Asia, Latin America) are balanced with those assigned to the control region (Europe) on high school test scores and prior language and travel experience. Those assigned to the treatment region report greater interest in global development and poverty, but no difference in support for government aid or higher immigration, and no difference in personal international donations, volunteering, or other involvement.

Here's the link to the paper and the twitter discussion.