This book explores, through the lens of the conflict in Syria, why international law and the United Nations have failed to halt conflict and massive human rights violations in many places around the world which has allowed tens of millions of people to be killed. The book focuses on the problems of international law and the UN and, in the context of the many enforced disappearances and arbitrary detentions in Syria, why nothing has been done to deal with a rogue state that has regularly violated international law. It examines why the responsibility to protect (R2P) has not been applied and why it ought to be used, generally, and in Syria. The book will be a valuable resource for students, academics and policy-makers working in the areas of public international law, international human rights law, political science and peace and security studies.