Vermont senator Bernie Sanders, 76, came of age at a time when the left was devoted to class struggle, not ethnic conflict. As a result, the self-proclaimed democratic socialist has tripped up time and again on the issue of immigration.

At the outset of his presidential campaign in 2015, Sanders took a sensible line on open borders for a candidate ostensibly devoted to improving the economic lot of working class Americans. In a summer 2015 interview with Ezra Klein of Vox, he expressed strident opposition to open borders: