States invariably justify using force extraterritorially by reference to their right of self-defence. In doing so, they accept that the exercise of this right is conditioned by the customary international law requirements of necessity and proportionality. However, these requirements are notorious for being normatively indeterminate and operationally complex. As a breach of either requirement renders ostensibly defensive action unlawful, increased determinacy regarding their scope and substance is crucial to how international law constrains military force. This book examines the conceptual meaning, content, and practical application of necessity and proportionality as they relate to the right of self-defence following the adoption of the UN Charter in 1945. It provides a coherent and up-to-date description of the applicable contemporary international law and proposes an analytical framework to guide its operation and appraisal. This book argues that necessity and proportionality are conceptually distinct and must be applied in the foregoing order to avoid an insufficient 'catch-all' description of legality or illegality. Necessity determines whether defensive force may be used to respond to an armed attack and where it must be directed. Proportionality governs how much total force is permissible and prohibits excessive responses. Both requirements are shown to apply on an ongoing basis throughout the duration of an armed conflict prompted by self-defence. Compliance with necessity and proportionality ensures that the purposes of self-defence are met, and nothing more, and that defensive force is not unduly disruptive to third party interests and to international peace and security.

Yoram Dinstein's influential textbook is an indispensable guide to the legal issues of war and peace, armed attack, self-defence and enforcement measures taken under the aegis of the Security Council. This fifth edition incorporates recent treaties such as the Kampala amendments of the Statute of the International Criminal Court, new case law from the International Court of Justice and other tribunals, and contemporary doctrinal debates. Several new supplementary sections are also included, which take into account recent conflicts around the world, and consideration is given to new resolutions of the Security Council. With many segments having been rewritten to reflect recent State practice, this book remains a wide-ranging and highly readable introduction to the legal issues surrounding war and self-defence.

In NATO Rules of Engagement, Camilla Guldahl Cooper offers clarity on a topic prone to confusion and misunderstanding. NATO rules of engagement (ROE) are of considerable political, strategic and operational importance, yet many of its concepts lack clarity. The resulting ambiguity may be detrimental for people involved and for mission accomplishment. Through a thorough analysis of the concept, purpose, development and use of NATO ROE, Cooper contributes to improved understanding and implementation of NATO ROE. The book covers all use of force categories and relevant law relating to the use of force during armed conflicts, including the complex concepts of hostile act and hostile intent, direct participation in hostilities, and the increasing reliance on self-defence during armed conflict.

"Necessity and proportionality occupy a firm place in the international law governing the use of force by states. Perhaps most importantly for practical purposes, the exercise of the right of self-defense, as recognized in Article 51 of the United Nations Charter, is subject to the requirements of necessity and proportionality, as the International Court of Justice determined in the Nicaragua case. Necessity and proportionality are also firmly anchored in the international law governing armed conflicts. In its Nuclear Weapons Advisory Opinion, the International Court of Justice even referred to one articulation of the idea of necessity, that directed against the causing of unnecessary suffering, as one of two "cardinal principles" of this body of law. However, beyond statement in such general terms, the realms of uncertainty and controversy soon begin. It is far from clear, for example, how to distinguish with precision between necessity and proportionality in the international law on self-defense and, in immediate connection herewith, what it means precisely to say that forcible action taken in the exercise of self-defense must be proportionate. It is all the less clear what legal significance, if any, necessity and proportionality possess in other contexts of the international law governing the use of force"--

Self-defense and the right to go to war. Originally published: New York: Praeger, [1958]. xv, 294 pp. Bowett observes that the use or threat of force by any state can be a delict, an approved sanction, or a measure taken in self-defense. He examines the evolution of self-defense doctrine in the nineteenth and early-twentieth centuries, with the assumption of the existence of a state's unlimited 'right' to go to war. He then attempts to outline the limited and provisional effects of this right under the U.N. Charter. This book was written after Bowett's term as a United Nations legal officer from 1957-1959. "Throughout the work there is a refusal to dogmatize or to state in absolute terms any aspect of the 'privilege' of self-defence in its present context. (...) [Bowett] is to be congratulated on producing a timely and scholarly survey of one of the most fundamental, and often abused, sovereign rights known to international law." --K.R. Simmonds, British Year Book of International Law 34 (1958) 432. SIR DEREK WILLIAM BOWETT [1927-2009], an international lawyer, was President of Queens' College, Cambridge from 1969-1982 and Whewell Professor of International Law, Cambridge, from 1981-1991. He was awarded a CBE in 1983 and a knighthood in 1998. He is the author of The Law of International Institutions (1963), United Nations Forces: A Legal Study (1964), The Law of the Sea (1967), The Search for Peace (1972) and The International Court of Justice (1996).

Aesthetic philosophy and the arts offer an innovative and attractive approach to enhancing international law in support of peace.

Provides a multi-perspective study of the international law on self-defence against non-State actors.

While an abundance of literature covers the right of states to defend themselves against external aggression, this is the first book dedicated to the right to personal self-defense in international law. Dr. Hessbruegge sets out in careful detail the strict requirements that human rights impose on defensive force by law enforcement authorities, especially police killings in self-defense. The book also discusses the exceptional application of the right to personal self-defense in military-led operations, notably to contain violent civilians who do not directly participate in hostilities. The author establishes that international law gives individuals the right to forcibly resist human rights violations that pose a serious risk of significant and irreparable harm. At the same time, he calls into question prevailing state practice, which fails to recognize any collective right to organized armed resistance even when it constitutes the last resort to defend against genocide or other mass atrocities.

There has been considerable debate in the international community as to the legality of the forceful actions in Kosovo in 1999, Afghanistan in 2002 and Iraq in 2003 under the United Nations Charter. There has been consensus, however, that the use of force in all these situations had to be both proportional and necessary. Against the background of these recent armed conflicts, this 2004 book offers the first comprehensive assessment of the twin requirements of proportionality and necessity as legal restraints on the forceful actions of States. It also provides a much-needed examination of the relationship between proportionality in the law on the use of force and international humanitarian law.

Examines the difficulties in applying international law to recent armed conflicts known as 'new wars'.