In the field of migration politics, a dominant rhetoric argues that liberal immigration and asylum policies must be avoided because they will inevitably lead to anti-immigration backlashes that exacerbate the very conditions they were supposed to remedy. Drawing on the work of German sociologist Heinrich Popitz and empirical data on the aftereffects of the European migration crisis, the article criticizes this "rhetoric of reaction" (Albert Hirschman) for ignoring the many variables shaping the consequences of more open borders. Backlashes to immigration are real and pose a constraint for liberal immigration policies, but these backlashes are not necessarily politically successful. Societies react neither uniformly nor automatically to rising immigration. A critical variable is the fear engendered by the (real, expected, or imagined) arrival of large numbers of migrants, and this fear can be either ramped up to paranoid levels or calmed by a politics of hope aimed at restoring what Popitz called the "human openness to the world."