When an Olive Branch Pays Off at Home: Polarization, Partisan Competence, and Public Support for Peace

What domestic political benefits do leaders derive from successful peace initiatives with a foreign adversary? Existing research emphasizes how adversary cooperation softens enemy images and increases public support for reconciliation, but pays less attention to how such concessions operate as political assets domestically. This paper examines how partisan polarization conditions the domestic political returns to adversary cooperation for incumbent leaders. I argue that polarization intensifies partisan interpretations of diplomatic outcomes by converting foreign concessions into signals of incumbent party's competence. When a leader secures reciprocal cooperation, ruling-party supporters are likely to interpret the outcome as a partisan achievement, increasing their support for rapprochement. Cross-partisans may also shift toward support as the incumbent’s diplomatic success undermines confidence in their own party’s competence. I test these expectations using an original survey experiment centered on U.S.–DPRK rapprochement during the first Trump administration. The results indicate that polarization priming amplifies Republican support for reconciliation by strengthening perceptions of partisan competence, while Democrats exhibit a modest increase in support, accompanied by declining confidence in their party’s competence. Overall, the findings demonstrate that domestic political conflict fundamentally shapes whether and how foreign signals are translated into domestic political assets or liabilities within partisan competition.