Addressing Challenges to Supranational Integration: The case of the Euro

Why has public support for the European Monetary Union (EMU) reached record highs despite persistent strains on international cooperation? In a context marked by increasing challenges to international cooperation, support for the euro has (paradoxically) reached record highs in recent years. This article argues that the rising legitimacy of the Economic and Monetary Union can be partly explained by its gradual re-balancing, defined as the growing integration of social concerns in its macroeconomic agenda. Drawing on the policy feed-back literature, I posit two mechanisms: (1) Partisan accommodation, as challenger parties shift from principled opposition to contestation over the EMU’s substantive policy orientation; and (2) Public receptiveness, as citizens aware of the EU’s evolving policy mix reconsider the extent to which the common currency project aligns with their ideological preferences. I substantiate these claims using a mixed-methods design combining longitudinal Eurobarometer data (2004-2021), party-level evidence from the Euandi surveys (2019, 2024), and novel survey data from the 2025 ERC SOLID study across twelve EMU countries. Taken together, these analyses show that awareness of EMU rebalancing is associated with stronger support for the euro and that this effect is strongest amongst among citizens whose preferred parties moderated their opposition to the EMU. Contrary to early accounts that viewed the apolitical character of supranational institutions as a necessity to guarantee their maintenance, these findings suggest that visible, redistributive and socially responsive policy change can produce the political feedback loops that underpin their legitimacy.