Populist Diplomacy and the Transition from Law-Making Treaties to Contractual Treaties

A growing apprehension towards economic globalisation, international institutions, and constraints on sovereign political authority has accompanied the rise of populist diplomacy. By linking domestic anti-establishment sentiment with sovereignty-centred narratives, populist diplomacy often frames multilateral legal commitments and international institutions as constraints on national political choice. This research paper examines how this type of engagement affects treaty-making and institutional structures, with particular reference to the United Nations (UN) Charter, World Trade Organisation (WTO) agreements, the Rome Statute, and other major human rights and environmental regimes. This paper argues that the legal practices associated with populist diplomacy, which include contestation against international institutions, selective cooperation, withdrawal strategies and preferences for flexible arrangements, are not inherently populist. Instead, the significance of populist diplomacy is elucidated by the way in which these legal practices are configured and justified as part of a broader sovereignty-centred challenge to international legal authority. Against this backdrop, this research paper examines the appeal of contractual forms of cooperation as an alternative to institutionalised forms of cooperation; in that states retain greater control, flexibility, and reversibility. The argument put forward is not that contractual arrangements are inherently populist, but rather that their use as alternatives to more institutionalised forms of cooperation may reinforce existing pressures towards fragmentation within the international legal order. The paper concludes that the challenge posed by populist diplomacy goes beyond withdrawal from formal treaties; contributing to the gradual weakening and contestation of the institutions and interpretive processes that give international legal commitments their practical effect.