These are interesting times at the constitutional margins. Questions about where the Constitution takes up and leaves off are more frequently in play; one can no longer so readily assume the Constitution to supply an authoritative metric as we confront prominent cases of nonapplication. At the same time, the increasing robustness of international norms has prompted a vigorous reconsideration of their relationship to domestic ones. Where the twentieth century was marked by deep segmentation among national legal regimes, with minimal transboundary interpenetration, recent years have seen the advent of complex, overlapping regimes: subnational, national, regional, and global, public, and private. Sorting out these regimes, and finding the place of the Constitution among them, poses a a foundational challenge for America's constitutional future. These questions have until recent years also been at the margins in the academy, where they have not attracted much direct scholarly inquiry. As in related disciplines, constitutional theory has taken the state and the national community as exogenous quantities, whose edges are (in effect) assumed congruent with those of the universe. Straddling contexts have long been absent from the constitutional canon. The academic mainstream has, for instance, taken little interest in the constitutional puzzles of immigration and international law. Scholars in those and related areas have suffered a sort of stepchild status among constitutional-law theorists, their concerns dismissed as constitutional anomalies rather than studied as constitutional keys.
Peter J. Spiro,
The Impossibility of Citizenship,
Mich. L. Rev.
Available at: https://repository.law.umich.edu/mlr/vol101/iss6/6