Illiberal and irrational? Trump and the challenge of liberal modernity in US foreign policy

Building on a growing body of literature on the application of Morgenthau's ethics to post-Cold War US foreign policy, this article applies Morgenthau's concept of irrationality to Trump's foreign policy. Based on this application, the article highlights the limit of rationality in Morgenthau's theoretical analysis. Specifically, the article argues, pace neo-realist critiques of 'liberal hegemony', that Trump reveals an empirical puzzle: US foreign policy can bebothirrationalandilliberal simultaneously in the pursuit of nationalistic universalism. This is the case, the article argues, because nationalistic universalism in Morgenthau's analysis is not rooted in liberalism per se but the dynamics of liberal modernity. The Trump puzzle thus reveals an on-going tension between rationality and liberal modernity in Morgenthau's theoretical analysis: rationality offers an insufficient tool to take upon the challenge of liberal modernity from which Trump's nationalistic universalism stems. This, the article concludes, leaves Morgenthau's concept of interest 'defined in terms of power' open to misappropriation to ends contrary to their original aim: furthering nationalistic universalism, rather than limiting power.