You might expect that I, as an immigrant and as an economist who favors the free movement of labor, would find the idea of open borders to be an obviously good policy. If you also learned that in 1977, the Immigration and Naturalization Service tried to deport me, you might think that I would also be emotionally, and not just intellectually, in favor of open borders. At times I have been.

At other times, though, my enthusiasm for open borders has flagged. When I didn’t know a lot about the facts, I worried that a large number of immigrants would come here for welfare or would, once they became citizens, vote for an even larger amount of government interference than we currently have. I didn’t worry about crime because I knew that immigrants commit crime at a lower rate than non-immigrant Americans. The work of my co-blogger Bryan Caplan and others persuaded me that my fears were largely unjustified. In fact, my new learning motivated me to write a Defining Ideas article titled “The Case for More Immigration.” Now Caplan’s latest book, Open Borders: The Science and Ethics of Immigration, has reduced those fears even more. Caplan considers virtually every argument against open borders and demolishes each with a figurative Howitzer. I do, however, have two criticisms of his book—one of substance, and one of tone in a particular footnote.

This is from David R. Henderson, “A Graphic Case for Open Borders,” Defining Ideas, November 13, 2019.