Between soldiers and cops: the transnational boundary work of militarization in Mexico

Abstract Democracies around the world increasingly deploy their militaries in domestic law enforcement, fuelling normative and practical concerns about blurred boundaries between the competence of police and soldiers. We examine the boundary work of state justification for militarized policing, investigating its interactions with the transnational governance of security. We argue that the militarization of policing in Latin America has been justified through multiple boundary reconfigurations: beyond its mere ‘blurring’, the police–military boundary has also been variously bridged, redrawn or maintained. Moreover, we argue that these practices are discursively enabled by transnational security logics. We demonstrate these claims by investigating the militarization of policing in Mexico between 1983 and 2024, and its relationship with US–Mexico security cooperation. We analyse data on US security assistance and foreign military training, as well as the national development plans created by Mexican governments. By examining the transnational making of Mexico's militarization, we shed light on how police, soldiers and the boundary between them are constituted transnationally. We thereby contribute to current debates on security policy and assistance by exploring the multiple boundary practices involved in the justification of militarized policing, and by demonstrating how these practices are co-constituted with cooperation arrangements that help circulate and legitimize threat conceptions and associated prescriptions.