Sovereignty remains one of the most contested political issues in the discourse about populism. Prominent scholars on the American left have made the study of Jewish ethics a crucial component of campaigns to discredit sovereignty as a political ideal. Against these scholars, Julie E. Cooper contends that the fixation upon Jewish values is liable to hinder the development of a forceful rejoinder to sovereignty’s defenders. To temper the enthusiasm for ethics as a framework for arbitrating conflicts over sovereignty, she revisits an internal Zionist debate surrounding the wisdom of investing political energy in projects of ethical cultivation. Drawing on Jakob Klatzkin (1882–1948), she argues that critics of sovereignty should downplay ethics, focusing instead on defending the political viability of non-sovereign regimes. The challenge is to combat the poverty of imagination when it comes to envisioning political agency beyond the nation-state.