The “Great Powers” and The Formation of International Law

Abstract The US, Russia, and China – the current “Great Powers” – often disagree over primary rules of international law, such as the scope of self-defence in response to an armed attack. Such disagreements over primary rules can often be explained in traditional realist fashion, because powerful States generally interpret international law in a manner that reflects and advances their interests. But that is not always the case. In some situations, Great Power disagreements over primary rules are driven less by realpolitik than by very different understandings of the formal sources of international law – the sources that determine what qualifies as a primary rule. Most comparative international law scholarship has focused on how the Great Powers view primary rules, ignoring how the US, Russia, and China disagree over the formal sources of international law. This article focuses on disagreements in the latter category. After a brief introduction in Part I, Part II explains how the US, Russia, and China perceive the formal sources of internal law in abstracto – which they privilege and why, methodological inconsistencies in how they understand and apply a particular source, and so on. Part III then examines four areas of international law in which different perceptions of the formal sources have a significant effect on how the US, Russia, and China perceive the primary rules: the jus ad bellum, the jus in bello, arms control, and cyberspace. Some concluding remarks follows in Part IV.