Toward Stronger Rule of Law Against Attempts to Acquire Territory by Force: A Practitioner’s View

This book addresses one of the most pressing issues of international law in recent years, attempts to acquire territory by force. When powerful States are not satisfied with territorial status quo and are unwilling to give up their interests for peace, there is an inherent difficulty in stopping their attempts to acquire territory by force. This book will review the efforts made so far to stop such attempts, examine the current state of rules of international law against them, and explore how rule of law can be strengthened. It is written by a former legal advisor who participated in the proceedings of the International Court of Justice (ICJ) for the Advisory Opinion issued on July 19, 2024. Based on the approach often taken by practitioners working for governments, who tend to appreciate narrative based on persuasive evidence and logic and increasingly rely on views expressed by courts and tribunals, the scope of the prohibition of acquisition of territory by force and, as an alternative rule, the prohibition of use of force is examined. Acts constituting attempts to acquire territory by force and their contexts which contribute to the violation of the two prohibitions will be analysed, and cases likely to amount to their violation will be explored. It will also discuss whether States can acquire territory by use of force in self-defence and examine obligations arising from the violation of the prohibition of acquisition of territory by force for third States.

Mr. Tomohiro Mikanagi is currently holding the position of Ambassador Extraordinary and Plenipotentiary, Deputy Permanent Representative of Japan to the United Nations. He also has the title of Ambassador-at-Large for Cooperation on International Law. He studied international law at the University of Tokyo (BA) and University of Cambridge (Diploma and LL.M). He was also a visiting fellow at the Lauterpacht Centre for International Law in Cambridge. He has been publishing various articles on international law in a personal capacity, and this book is also written in this capacity.

In his diplomatic career, Ambassador Mikanagi has had extensive experience in the area of international law. He has served for more than ten years at the International Legal Affairs Bureau of the Japanese Ministry of Foreign Affairs, and held the titles of Deputy Director and Director of the International Legal Affairs Division, Deputy Legal Advisor and Legal Advisor. He has also served in London and Beijing as a diplomat.