Unfortunately, badly needed market liberalization in much of Africa and many other places has been slight to nonexistent. Trump may have these countries in mind when he thinks about immigration, but the fault lies not in the people but in their rulers and whomever those rulers rely on for economic advice. The least we can do is let desperate people escape to America.
Immigration is right (as well as a right). It is also good. Immigrants get to make better lives, and how they do so -- by gaining access to better tools as well as more freedom -- can't help but benefit everyone else, if not immediately, then certainly just a short way down the road. Forcing people to live under repressive regimes is cruel as well as self-destructive.
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