Introduction: reopening the case of Leo Strauss -- Warrior morality and the fate of civilization: Strauss's encounter with Carl Schmitt and German nihilism -- Legitimacy and legality, thinking and ruling in the closed society and the world state: the Strauss/Kojแeve debate -- Strauss's Machiavelli: fallen angel and theoretical man -- Thucydides versus Machiavelli: a moral-political horizon of war and law -- Justice and progress: Strauss's assessment of modern international law -- Conclusion