Sovereignty & the Responsibility to Protect: A New History. By Luke Glanville. Chicago and London: Chicago University Press, 2014. 294 pp., $95.00 hardcover (ISBN-13: 978-0-226-07689-8), $32.50 paperback (ISBN-13: 978-0-226-07692-8). In the natural sciences, it is customary for theories to be tested and retested, falsifiability being one of the touchstones of academic rigor. In the social sciences, by contrast, it is common for ideas to simplify and ossify, with acceptance and repetition degrading them into cliches. So it is with a term like “sovereignty,” which is so loaded with significance that a precise and agreed-upon definition in politics or law has long been dismissed as unlikely. In the absence of such a definition, its use in at least some fields of International Relations (IR) has been reductionist—exemplified by the “billiard ball” model of states that are thought to interact with one another as billiard balls do on a table. Shiny and smooth, the surface of these billiard balls is all that matters to international society, ignorant of and irrelevant to what happens inside. In such a conception of sovereignty, responsibility for how the state is run lies with the sovereign alone. “L'etat,” as Louis XIV may or may not have said, “c'est moi.” Wielding not a cue but a hammer, Luke Glanville successfully demolishes this caricature in his historical survey of sovereignty, building on a doctoral thesis supervised by Alex Bellamy and Richard Devetak. His argument, which extends back to the emergence of sovereignty in early modern Europe, is that sovereignty has always entailed aspects of responsibility as well as authority. Glanville's more specific aim is to challenge the idea that there is anything “new” about the most recent perceived challenge to the “traditional” conception of sovereignty: the responsibility to protect. This doctrine emerged from the aftermath of the 1999 Kosovo intervention and comprises two key principles that were embraced by all members of the United Nations in 2005: first, …