Issue framing, political identities, and public support for multilateral vaccine cooperation during Covid-19

Research shows that information cues influence public opinion on international cooperation, yet it is unclear whether all cues are equally effective in the context of a global crisis. This paper sheds light on this issue by analysing how frames in public discourse influence support for multilateral vaccine cooperation during Covid-19. Building on research on in-group favouritism, decision-making under uncertainty, and public support for multilateralism, the paper argues that frames emphasizing vaccine nationalism are more potent than those emphasizing international cooperation and that nationalist political identities moderate these framing effects. An original survey experiment in the United Kingdom confirms this argument and shows that public support for multilateralism is substantial but vulnerable. A vaccine nationalism frame reduces support for multilateralism, while an international cooperation frame has no effect. Moreover, ‘Brexit identities’ moderate this framing effect, with ‘Leavers’ being more susceptible to the detrimental effect of the vaccine nationalism frame than ‘Remainers’.