Military Alliances and Public Support for War

2021/02/25 by Michael Tomz, Jessica Weeks, Jessica L P Weeks · 2 voices · 9 citations
Social Sciences · #International Relations and Foreign Policy #Social and Intergroup Psychology #Terrorism, Counterterrorism, and Political Violence

paper · pdf · doi:10.1093/isq/sqab015

openalex publication_date 2021/02/25 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/25

Abstract

Abstract How do military alliances affect public support for war to defend victims of aggression? We offer the first experimental evidence on this fundamental question. Our experiments revealed that alliance commitments greatly increased the American public's willingness to intervene abroad. Alliances shaped public opinion by increasing public fears about the reputational costs of nonintervention and by heightening the perceived moral obligation to intervene out of concerns for fairness and loyalty. Finally, although alliances swayed public opinion across a wide range of circumstances, they made the biggest difference when the costs of intervention were high, the stakes of intervention were low, and the country needing aid was not a democracy. Thus, alliances can create pressure for war even when honoring the commitment would be extremely inconvenient, which could help explain why democratic allies tend to be so reliable. These findings shed new light on the consequences of alliances and other international legal commitments, the role of morality in foreign policy, and ongoing debates about domestic audience costs.

Citations

• When Backing Down Is the Right Decision: Partisanship, New Information, and Audience Costs
• Audience Costs among the British Public: The Impact of Escalation, Crisis Type, and Prime Ministerial Rhetoric
• Reevaluating Alliance Reliability
• The Cost of Empty Threats: A Penny, Not a Pound
• Defending International Norms: The Role of Obligation, Material Interest, and Perception in Decision Making
• International Law and State Behavior: Commitment and Compliance in International Monetary Affairs
• Moral Support: How Moral Values Shape Foreign Policy Attitudes
• Domestic Political Audiences and the Escalation of International Disputes
• Unpacking the Black Box of Causality: Learning about Causal Mechanisms from Experimental and Observational Studies
• Domestic Audience Costs in International Relations: An Experimental Approach
• Public Opinion and the Democratic Peace
• Promises or Policies? An Experimental Analysis of International Agreements and Audience Reactions
• Mechanisms of Morality
• Public Opinion and Decisions About Military Force in Democracies
• Reliability, Reputation, and Alliance Formation1
• Survey Design, Order Effects, and Causal Mediation Analysis
• The moderator–mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations.
• Intuitive ethics: how innately prepared intuitions generate culturally variable virtues

Cited by

• Manipulating Public Beliefs about Alliance Compliance: A Survey Experiment
• U.S. Military Should Not Be in My Backyard: Conjoint Experiments in Japan
• Pre-war experimental evidence that Putin’s propaganda elicited strong support for military invasion among Russians
• Why reassuring allies is harder than deterring adversaries in extended deterrence: Evidence from US extended deterrence for South Korea
• Historical Analogies and Public Support for Foreign Policy Action
• Unraveling Americans’ Selective Sympathies Toward Israelis and Palestinians
• Scapegoating Your Ally: How Leaders Deflect Audience Costs by Blaming Allies for Not Supporting Them in International Crises
• The Politics of Alliance Cohesion: Experimental Evidence on American Attitudes toward Corrective Measures in Security Partnerships
• Judicialization and Public Support for Compliance with International Commitments

Discussions

• 同盟条約の存在によって、アメリカ国民が海外に介入する意欲が大幅に高まることを実験的アプローチで示した研究です。 民主主義国との外交における条約の意義を改めて示しています。 Military Alliances and Public Support for War doi.org/10.1093/isq/... [bsky, 4 points, 1 comments]
• this week, replications are all the rage, so we are happy to add one of our own: we successfully replicated doi.org/10.1093/isq/... by Tomz & Weeks in USA, as well as in UK, Russia, China, India & Bra [bsky, 0 points, 0 comments]

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