Religions are reemerging in the social, political, and economic spheres previously occupied and dominated by secular institutions and ideologies. In the wake of crises exposing the limits of secular modernity, religions have again become significant players in domestic and international politics. At the same time, the Catholic Church has sought a "holy alliance" among the world's faiths to recentralize devout influence, an important, albeit little-noticed, evolution in international relations. Holy Wars and Holy Alliance explores the nation-state's current crisis in order to better understand the religious resurgence's implications for geopolitics. Manlio Graziano looks at how the Catholic Church promotes dialogue and action linking world religions, and examines how it has used its material, financial, and institutional strength to gain power and increase its profile in present-day international politics. Challenging the idea that modernity is tied to progress and secularization, Graziano documents the "return" or the "revenge" of God in all facets of life. He shows that tolerance, pluralism, democracy, and science have not triumphed as once predicted. To fully grasp the destabilizing dynamics at work today, he argues, we must appreciate the nature of religious struggles and political holy wars now unfolding across the international stage.