A largely dysfunctional American immigration system is only poorly explained by simple depictions of the political economy of lawmaking on this issue, blaming factors such as functional economic policy-setting, longstanding public attitudes, explicit presidential decisions, or general gridlock. Instead, the structure of immigration law emerges from intersecting effects of three separate dynamics — statutory compromises rooted in the political economy of lawmaking, organizational practices reflecting the political economy of implementation, and public reactions implicating the responses of policy elites and the larger public to each other. Together, these factors help constitute an immigration status quo of continuing legal controversies as well as powerful obstacles to change. (1) Particularly since 1986, American immigration statutes have created a legal arrangement essentially built to fail, giving authorities regulatory responsibilities that were all but impossible to achieve under existing law. (2) Implementation has been characterized by organizational fragmentation, with policy changes involving one agency producing externalities not owned by that agency, and limited presidential power to change enforcement or implementation. And (3) the interplay of unrealistic statutory goals, enforcement, and public attitudes engenders a dynamic of polarizing implementation, where agencies’ incapacity to enforce existing law tends to spur polarized political responses producing legislation that exacerbates agency difficulties in meeting public expectations, without giving interested parties enough of a reason to support an alternative. The resulting process over the last few decades persistently favored expansion in the provision of border enforcement resources. This development is widely supported or at least tolerated by most political actors, even though it fails to address the core institutional problems of the status quo. Beyond what these developments tell us about immigration law, they also reveal much about (a) how statutory entrenchment in the United States is affected by political cycles capable of eroding the legitimacy of public agencies, and (b) how powerful nation-states control, in limited but nonetheless significant ways, the transnational flows affecting their well-being and security.