Two Faces of Foreign Affairs Federalism and What They Mean for Climate Change Mitigation

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President Trump has done the impossible: he has made the international community enthusiastic about U.S. federalism. Even as they express dismay at Trump's plan to abandon the Paris Agreement, foreign leaders and internationalists have praised the efforts of U.S. states and cities to combat climate change mitigation in accordance with the Agreement's goals. These leaders are responding to what I will call the outer face of foreign affairs federalism—the direct international engagement undertaken by U.S. states and cities. This outer face has gained visibility in recent years, spurred on not only by the exigencies of climate but also by developments in legal practice. Less noticed internationally but of great practical importance is the inner face of foreign affairs federalism—the ways in which U.S. states and cities interact with the federal government. In this contribution, I first describe these two faces of foreign affairs federalism as they relate to climate and then suggest some ways in which foreign leaders and internationalists could expand the outer face and respond to the inner face.


federalism, foreign affairs, climate change, climate change mitigation

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AJIL Unbound