This article represents the first part of a series of three, which examines the concept of federalism as related to foreign policy, from an International Relations (IR) and Foreign Policy Analysis (FPA) perspective. The first one is dedicated to the explanation of the reference framework, theoretical and practical, where the work of Clarence Streit is pivotal together with the “Federalist papers”. The following article will explore two dimensions of this relationship, which have been handled frequently separately for federalism and foreign policy, and especially from a domestic perspective rather than an external analysis: citizens’ participation and sovereignty. In the last article, the dimensions investigated will be global governance and public diplomacy, in which the adaptivity of federalism as a foreign policy tool emerges as related to the combination of self-rule and shared rule, both necessary to communicate and coordinate with the outside. Today, all these dimensions are challenged in different ways from the past, due to systemic dynamics, like the emergence of multipolarism at a global level, and unpredictable and transnational variables like the rise of the internet and climate change.
