War and Responsibility

Scholars and policymakers bemoan an imperial presidency in the war powers context, where the unilateral use of force is frequently interpreted as evidence of an unconstrained executive. Focusing on the strong blame avoidance incentives faced by politicians in the military intervention setting, I develop a model of the war powers focused on “Loss Responsibility Costs.” It suggests that presidents only risk full-scale war when they have the political cover provided by formal authorization, which forces lawmakers to share responsibility. Smaller interventions, in contrast, are frequently undertaken unilaterally because having the president act alone is consistent with congressional preferences for blame avoidance. Novel sentiment data based on tens of thousands of congressional speeches supports the claim that when the president acts unilaterally, they almost always act alongside lawmaker support, who favor intervention but avoid formally endorsing the endeavor. Altogether, it suggests legislators’ influence over war is stronger than commonly appreciated.