Explaining Public Demands for Border Militarization

The militarization of border control is a defining feature of contemporary international politics. Why do states flock toward these policies despite their questionable efficacy? We theorize that border militarization stems in part from public reactions to the threat of international and domestic decline. We test this argument with two conjoint experiments that randomize the implementing agency, strategy, costs, and effectiveness of different policies. First, we evaluate whether the public has a baseline preference for militarization, holding constant the material costs and consequences of the border policy. Second, we prime threats of decline—in terms of either America’s dominant status in the world or the majority position of white-identifying Americans within the U.S.—and track changes in preferences for militarized border policies. The results indicate that both threats of decline can increase support for border militarization, with important partisan differences. Border militarization plausibly stems from the reactionary politics of domestic audiences.