The law of the use of force and self-defence continues to be a source of divergence and contestation in the practice of states and scholarly approaches. Our research in this area aims to take stock of the evolution of jus ad bellum in a shifting world order with the rise of non-state actors, spread of terrorism, and the challenges of increasing unilateralism in international affairs. More broadly, we also explore issues of collective security, sanctions and peacekeeping.

Highlights from our work in this area:

Max Planck Trialogues on the Law of Peace and War: Self-Defence against Non-State Actors

In this book, self-defence against non-state actors is examined by three scholars whose geographical, professional, theoretical, and methodological backgrounds and outlooks differ greatly. The novel scholarly format brings to light the cultural, professional and political pluralism which characterises international legal scholarship and exploits this pluralism as a heuristic device. This multiperspectivism exposes how political factors and intellectual styles influence the scholarly approaches and legal answers and the trialogical structure encourages its participants to decentre their perspectives. By explicitly focussing on the authors’ divergence and disagreement, a richer understanding of self-defence against non-state actors is achieved, and the legal challenges and possible ways ahead are identified. The book is published as part of the innovative Max Planck Trialogues on the Law of Peace and War and co-edited by Professor Christian J. Tams.


Editors: Mary Ellen O’Connell, Christian J. Tams, Dire Tladi

Publisher: Cambridge University Press

Publication date: August 2019

ISBN: 9781316641125