War today is a messy business, and not least for intellectuals. Once upon a time, we are often told—before 9/11, or perhaps before World War II—it was simpler. States waged wars while international law tried to humanize the fighting. But this has broken down as terrorism, civil wars, insurgencies, occupations, and humanitarian interventions pit states against nonstate actors. Such a narrative is as familiar as it troubling. And yet, Claire Vergerio argues, “almost every part of this is wrong” (253). In debunking popular intellectual myths about war, she aims less to restore our comfort with the present, than to trouble our rosy assumptions about the past.

Vergerio’s work is an intellectual history, focused on the sixteenth-century Italian jurist Alberico Gentili—or more particularly, on how later scholars revived his work in the nineteenth and early twentieth centuries. They did so, she argues, not so much to learn from Gentili as to invoke him. For British and American scholars like T.E. Holland and James Brown Scott, and later for the controversial, sometime Nazi jurist Carl Schmitt, international law and order revolved around the modern, sovereign state. Only the state was a legitimate actor; only states could go to war; and there were no grounds for judging any state’s causes “just” or “unjust.&rdq