Tom is a generalist international lawyer whose research interests include boundaries, the law of the sea, the use of force, investment protection, international trade, the procedure of international courts and tribunals, legal history, law and technology, and artificial intelligence and the law.
Tom’s books include Recognition of States (1999), Admission of States to the United Nations (2009), Aggression against Ukraine: Territory, Responsibility, and International Law (2015), On the Path to AI: Law's prophecies and the conceptual foundations of the machine learning age (with Damon Wischik, 2020), Arbitration: A Very Short Introduction (with Tom Schultz, 2021), and Nuclear Arms Control in Peril. Why the Nuclear Non-Proliferation Treaty Matters and How to Save it (2024).
He is a contributing author of the Max Planck Encyclopedia of Public International Law and is editor of the sections of the forthcoming 10th edition of Oppenheim’s International Law on recognition of states and governments, state succession, neutrality, decolonization, and trade and customs unions.
Among Tom's other forthcoming or recently published works are Sovereignty Disputes and the United Nations Convention on the Law of the Sea. A public order perspective (Manchester University Press, forthcoming 2025) and ‘Patents, Competition & Security: Commercializing Innovation in the Global Ecosystem for 5G & IoT,’ with F Scott Kieff in Jonathan M Barnett & Sean M O'Connor (eds.), 5G and Beyond: Intellectual Property and Competition Policy in the Internet of Things (Cambridge UP, 2023).
Tom served from 2016-2019 as a research exercise leader of the Leverhulme Centre for the Future of Intelligence, addressing artificial intelligence and autonomous weapons. In 2022-2023, he served as a supervisor for the Centre's MSt in AI Ethics and Society. The United States designated Tom to the roster of the Permanent Court of Arbitration in 2021. While on leave from Cambridge (2019 to 2021), Tom served as Senior Advisor for Strategic Planning in the Bureau of International Security and Nonproliferation in the U.S. Department of State.
In 2023, among other speaking events, Tom addressed audiences at the Davos World Economic Forum, the Munich Security Conference, and the Yalta European Strategy Summit (Kyiv) on issues arising from Russia's aggression against Ukraine. He also recently addressed current issues of nuclear non-proliferation and the Treaty on the Non-Proliferation of Nuclear Weapons at events coordinated by the Nonproliferation Policy Education Center (NPEC). He served in 2022 as lead counsel to a Reparations Study Group convened by the New Lines Institute, in which capacity he was lead author of the Group's . Tom appeared as a witness in hearings of the U.S. Commission on Security and Cooperation in Europe (Helsinki Commission), Washington, DC (Sept. 23, 2023). In 2024, among other engagements, Tom gave the keynote address to NATO’s annual Operational Law Conference in the Hague, lectured at the 11th Annual Master Class of the Sir Geoffrey Nice Foundation in Dubrovnik, and convened a workshop in Cambridge on geopolitics and international law (with the Centre for Geopolitics).
Tom's undergraduate degree is in European History (Harvard, summa cum laude); his JD is from Yale; and he did his PhD (law) at Cambridge as a »ÆÉ«ÊÓƵ student.