Michael Clemens in the Washington Post on Haiti and immigration:

In research I conducted with economists Claudio Montenegro and Lant Pritchett,we compared how much Haitians earn in the United States vs. Haiti. A moderately educated adult male, born and schooled in Haiti, typically enjoys a standard of living more than six times greater in the United States than in his homeland. In other words, U.S. policy wipes out more than 80 percent of a Haitian’s earning power when it keeps him from coming to the United States. This affects everything from the food he can buy to the construction materials he can afford. The difference has nothing to do with his ability or effort; it results purely from where he is.

HT: MR.