Antinomies of Public and Private at the Foundations of International Investment Law and Arbitration

International investment law has in recent years become a topic of great practical and academic importance, as the thousands of international investment treaties have given rise to hundreds of investor-state arbitrations, and innumerable books and articles. But fundamental questions concerning the regulatory character of international investment law, and what its aims and objectives are, remain the subject of contestation reflected in a variety of policy debates and in competing historical narratives regarding the development of the field. This article contends that two 'public-private' distinctions or antinomies lie behind this indeterminacy, at international investment law's uncertain foundations-the first dealing with the characterization of international investment law as a form of 'public' or 'private' law, and the second dealing with the balance that international investment law strikes between 'public' and 'private' interests or objectives. A number of disputed issues in international investment law and arbitration, which are presented at the surface as merely technical problems, may in reality, it is argued, be products of these deeper underlying theoretical uncertainties.