摘要：The proliferation of state and local regulation designed to control immigrant movement generated considerable media attention and high-profile lawsuits in 2006 and 2007. Proponents and opponents of these measures share one basic assumption, with deep roots in constitutional doctrine and political rhetoric: immigration control is the exclusive responsibility of the federal government. Because of the persistence of this assumption, assessments of this important trend have failed to explain why state and local measures are arising in large numbers, and why the regulatory uniformity both sides claim to seek is neither achievable nor desirable. I argue that the time has come to devise a modus vivendi regarding participation by all levels of government in the management of migration. To do so, I provide a functional account of subfederal immigration regulation and demonstrate how the federal-state-local dynamic operates as an integrated system to manage contemporary immigration. The primary function of states and localities is to integrate immigrants into the body politic and thus to bring the country to terms with demographic change. This process cannot be managed by a single sovereign, and it sometimes depends on states and localities adopting positions in tension with federal policy. Given these dynamics, I offer a reformulation of existing federalism presumptions in the immigration context. These will not be primarily for application by courts, though courts should abandon constitutional or strong field and obstacle preemption theories in immigration cases. Instead, I offer a framework for federal and state lawmakers intended to restrain their impulses to preempt legislation by lower levels of government and to create incentives for cooperative ventures in immigration regulation. Counterintuitively, the changes wrought by international economic integration demand strong institutions beneath the national level. Immigration highlights this convergence of the transnational and the local. Only by assimilating our understandings of immigration federalism to this realization can we explain and harness the value of state and local regulation.
关键词：Cooperative federalism; Legislative powers; Emigration; Immigration; Government policy; States; Illinois; North Carolina; Iowa; Unauthorized migration; Preemption
