By drawing on ethnographic fieldwork with two grassroots groups that operate near the Arizona-Mexico border, this article illuminates how nativism is translated into day-to-day activism, often in ways that, while openly critical of the state, actually serve to strengthen the state. In contrast to conventional accounts that characterize nativist groups on the border as ‘vigilante’, I argue that the two groups which are the focus of this study, the Soldiers and the Engineers, seek to collaborate with state actors in an effort to restore the state’s exercise of what these groups consider to be legitimate violence in the borderlands. That is, the two groups enact nativism through popular sovereignty. Believing that the state’s ‘absence’ on the border is the result of an understaffed Border Patrol, the Soldiers fashion themselves into a civilian extension of the agency, taking pride in collaborating with locally stationed agents. Meanwhile, the Engineers find their entry point to the state through the ‘border security industrial complex’, hoping to work as private contractors for the Department of Homeland Security to restructure border surveillance. I conclude that we might expect popular sovereignty in other contexts where the state is perceived to be weak.