This book examines the character and legality of nation-states’ threats of force under international law, drawing its title from Article 2(4) of the United Nations (UN) Charter: “All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.” The article's wording seems straightforward enough: most statesmen recognize unlawful uses of force when they see them, and hundreds of legal works are available to help dissect any areas of ambiguity. But identifying prohibited threats of force—as legally serious as actual uses, according to the author—forms the question at the heart of this book. How should lawyers and statesmen identify and respond to illegal threats of force under the UN Charter?
Astride the intersection of war and diplomacy, this short and readable volume is the...