(iPoster) Election Night Impacts: U.S. Leadership and Allied Strategic Decisions

• In Event: Poster Session: Security and the Politics of Military Cooperation

Abstract

U.S. allies faced significant stakes in the 2024 presidential election, which featured two candidates with starkly divergent positions on alliance commitments and the broader international order. Alliance theory suggests that a member’s willingness to coordinate diminishes when its partner’s trustworthiness declines. However, the asymmetric structure of U.S.-led alliances may generate countervailing incentives, encouraging junior allies to deepen their investment in the relationship to retain the superpower’s attention and commitment. To test these competing perspectives, I conducted a survey experiment with roughly 1,000 Australian respondents on the eve of the election. The experiment included a control group and two treatment groups: one exposed to information about Kamala Harris’s support for alliances and her likelihood of becoming president, and the other exposed to Donald Trump’s skepticism toward alliances and his chances of returning to office. The outcome variables assessed Australians’ willingness to see their government align with U.S. leadership across three critical dimensions of great power competition: pre-committing Australia's military forces to U.S. efforts in a hypothetical conflict with China over China, criticizing China’s human rights record, and restricting China’s access to advanced technologies. The findings reveal that priming respondents with Donald Trump's possible return and his lack of commitment to alliances significantly reduced support for Australia aligning with U.S. foreign policy initiatives, highlighting the importance of trust and leadership signals in alliance dynamics. Heterogeneity analysis further indicates that this effect is concentrated among left-leaning respondents, with no significant impact observed among Australian conservatives. In light of the election result, the findings illuminate the international ramifications of leadership transitions within the U.S. and the erosion of U.S. credibility as a reliable ally and guarantor of the international order, particularly at a time when a rival great power actively challenges its authority.

Author

• Yan Liu, University of California, San Diego