Brexit Domino? The Political Contagion Effects of Voter-endorsed Withdrawals from International Institutions

This article examines the systemic implications of the growing popular backlash against international cooperation and analyzes how voter-endorsed attempts to withdraw from international institutions reverberate abroad. Observing other countries’ disintegration experiences allows voters to better assess the feasibility and desirability of such withdrawals. More positive withdrawal experiences encourage exit-support abroad, whereas negative experiences are likely to have a deterring effect. These contagion effects will be conditioned by the availability of information and voters’ willingness to learn. The article empirically examines this argument for the case of Brexit. It leverages original survey data from 58,959 EU-27 Europeans collected in six survey waves during the Brexit withdrawal negotiations and from a two-wave survey of 2,241 Swiss voters conducted around the first Brexit extension in spring 2019. It finds both encouragement and deterrence effects, which are bigger when respondents pay attention to Brexit and are dampened by motivated reasoning.