Freedom of Navigation in the UN Convention on the Law of the Sea: A Case Study of Japan's Maritime Jurisdictional Claims

Abstract

The UN Convention on the Law of the Sea (UNCLOS) formalizes many rules about the extent and type of jurisdiction that states are entitled to claim over the navigation of vessels at sea. Disagreement over the interpretations of those rules have been a growing source of contention, particularly among Asian states embroiled in disputes over “freedom of navigation.” Despite the significance of maritime legal claims in contemporary naval competition, however, international relations scholars have not sought to explain patterns in the maritime jurisdictional claims and enforcement behaviors of states. This paper proposes a theory for predicting states’ approach to freedom of navigation (FON). I hypothesize that states with military power projection capability and/or economic dependence on trade and imported energy will be more likely to advocate maximal freedom of navigation, while states with a historical memory of naval assault or invasion and/or a perception of threat from naval powers will be more likely to impose restrictions on FON near their coasts. Based upon combinations of these variables, I develop sixteen ideal state types that can be used to categorize states and predict the positions they will adopt on FON. After developing this theory, I conduct an initial case study of Japan, which my theory predicts would espouse a mixed position on FON. Drawing upon both primary and secondary research, including interviews conducted in fall 2017 with six American and 25 Japanese maritime legal experts and officials, I find that Japan’s positions toward FON are indeed mixed. Although the motivations for Japan’s positions largely accord with the predictions of my theory, my findings also highlight the singular importance of Japan’s alliance relationship with the United States in shaping the contours of its maritime jurisdictional claims.