ABSTRACT
While the fl ow of workers across national borders is not a new phenomenonafter all, it was responsible for the settlement of Australia, Canada, and the United States-immigration over the last two or three decades has signifi - cantly raised the share of the foreign-born in Europe and North America. For example, the share of the foreign-born in the European population rose from 6.8 percent in 1990 to 10.3 percent in 2015; in Canada, the share of the foreign-born rose from 15.7 percent to 21.8 percent over this period, while in the United States it rose from 9.2 percent to 14.5 percent. 1 The dramatic increase in the presence of immigrants, who frequently speak a different language and are often from poorer countries, has stimulated some angry calls for stricter limits or tighter “border-security” measures-particularly in the United States, which shares a long border with a much poorer country (Mexico) and attracts many workers who have not been able to secure an offi cial immigration visa. Proposals to impose stricter limits on immigration, including those to expel immigrants without work visas, are frequently justifi ed with arguments that immigrants lower the wages of natives or otherwise impose a fi nancial burden on the “host” country.
