The Logic of Border Fortification in the Global South

Abstract

Policymakers often justify border hardening as a response to insecurity. However, evidence for security-based explanations of border fortification is limited. Instead, research points to political economy drivers like cross-border income inequality, migration, and populism. I argue that these factors better characterize incentives for fortification in the Global North than in the Global South, where most border hardening has occurred. Among developing countries, two salient, security conditions help account for increasing fortification. First, countries harden their borders to interdict transnational militant networks, and particularly cross-border rebel sanctuaries. Second, the expansion of US aid and training programs for border security under the War on Terror has also spurred fortification. I find support for these hypotheses using new data on US border security assistance in an instrumental variables setting. Results highlight the heterogeneous motivations countries face with respect to border control, and the role of external assistance programs in shaping border security.

Keywords: Borders; Counterinsurgency; Foreign Aid; Security Assistance

JEL Classification: F35, F51, F52