The Trump presidency appears to personify, along with Britain’s vote to withdraw from the European Union, a sense of deep crisis in the United States-led liberal international order (LIO). The two states that conceived and constructed a whole array of international institutions after 1945 now seem to be rejecting that order, or at the very least, demanding that its institutions either be reformed or recalibrated to better suit their purposes. However, both developments may signal a new phase in the evolution of the international system—more nationalistic, statecentric and transactional, in which costs and responsibilities are more widely shared and where the electorate questions the costs versus benefits of the postwar liberal consensus. This crisis has long been evident: rising non-western states; global shifts in economic power; illiberal non-state actors; deep-seated problems with the legitimacy of political elites; as well as social and racial problems at home all signal enduring problems for US global leadership. ‘Liberal internationalism’ has long been one of the most influential approaches to the challenge of international order-making in the post-1945 system. The question today is: in an unstable and rapidly changing world and given the changing character of societies, how relevant is liberal internationalism as an ideological construct, a scholarly theory or a practical roadmap, in navigating a new and potentially non-western world order?