Looking specifically at immigrants’ effects on economic institutions, Benjamin Powell finds little to be concerned about. Natural experiments in Israel and Jordan in particular suggest that immigration does not lead to reduced economic freedom, and historical data from the United States corroborates this. Though the matter isn’t open and shut, the evidence needed to establish a likelihood of harm appears so far to be lacking.

Suppose that immigration skeptics are right, and that higher immigration levels threaten American institutions. That threat need not always come to fruition; in particular, if we suspect that it’s coming, we can prepare for it. Not only that, but economists have observed that higher immigration levels translate to substantially more wealth for both the immigrant and the host country. Ilya Somin argues that we can and should spend some of this new wealth on sustaining the institutions that help to create it.

Eric Kaufmann explains the mechanism by which immigrants degrade a host country’s institutions: Because they are of a different ethnicity, immigrants cause mistrust; labor unions in particular are weakened. This results in a relatively free market for labor, which lowers living standards for the working class. Beyond a certain level of fragmentation, even political parties come to be dominated by ethnic concerns, and ethnic parties corrode a society still further. The way to address these problems, says Kaufmann, is to limit immigration to the rate at which immigrants can assimilate to the host society.

Peter Skerry questions the relevance of Powell and Nowrasteh’s analysis to the United States, because the “quasi-natural experiments” they highlight—two large but discrete migrant flows in the Middle East—differ drastically from the prolonged U.S. experience of mass immigration, legal and illegal, that began in 1965 and has ramped up to the present day. More lax enforcement than explicit policy, this American “experiment” has led to an entrenched undocumented population of 10-11 million and provoked a backlash exacerbated by five aspects of the contemporary debate: 1) a rhetorically convenient but operationally simplistic distinction between “good” legal immigrants and “bad” illegal ones; 2) a deliberate blurring, by advocates, of the distinction between immigrants and refugees; 3) post-Cold War, globalist rhetoric of a “flat” and “borderless” world; 4) organizationally debilitated political parties that do not seek to assimilate newcomers as they once did; and 5) a media-driven politics that portrays immigrants, especially Hispanics, as having the same problems, and needs, as the poorest and most marginalized black Americans.