AbstractFrom bringing back waterboarding, to violating treaty obligations, to banning Muslims, Donald J. Trump has proposed numerous extralegal policies. We examine the implications of this disdain for legality, arguing that Trump's frequent hostility and indifference to legal rules and institutions paradoxically impede his capacity to enact his promises and damage international law. To situate Trump's legal politics, we draw comparisons with the Bush and Obama administrations. As constructivists note, the vitality of legal norms is dependent not just on one state's actions, but crucially on others’ reactions. While Trump has gone beyond his predecessors in rhetorically attacking international law, the backlash he generates limits the realization of his agenda in part due to his failure to convince others to violate the law or revise legal rules in novel ways. When the administration does reluctantly pursue legal justifications for controversial policies, it is better able to overcome legal constraints and political opposition.