And in his recent book, The Victory of Reason, Rodney Stark has further shown "How Christianity Led to Freedom, Capitalism, and the Success of the West." Similarly and prior to the rise of the secular nation-state in America, Alexis de Tocqueville documented in his 1835 volume, Democracy in America, the remarkable flexibility, vitality and cohesion of Christian-rooted liberty in American society with business enterprises, churches and aid societies, covenants and other private institutions and communities.

In his book, The Myth of Religious Violence: Secular Ideology and the Roots of Modern Conflict, William Cavanaugh similarly notes that for Augustine and the ancient world, religion was not a distinct realm separate from the secular. The origin of the term "religion" (religio) came from Ancient Rome (re-ligare, to rebind or relink) as a serious obligation for a person in the natural law ("religio for me") not only at a shrine, but also in civic oaths and family rituals that most westerners would today consider secular. In the Middle Ages, Aquinas further viewed religio not as a set of private beliefs but instead a devotion toward moral excellence in all spheres.

However, in the Renaissance, religion became viewed as a "private" impulse, distinct from "secular" politics, economics, and science. This "modern" view of religion began the decline of the church as the public, communal practice of the virtue of religio. And as Cavanaugh shows, by the Enlightenment John Locke had distinguished between the "outward force" of civil officials and the "inward persuasion" of religion. He believed that civil harmony required a strict division between the state, whose interests are "public," and the church, whose interests are "private," thereby clearing the public square for the purely secular. For Locke, the church is a "voluntary society of men," but obedience to the state is mandatory.

The subsequent rise of the modern state in claiming a monopoly on violence, lawmaking, and public allegiance within a given territory depended upon either absorbing the church into the state or relegating the church to a private realm. As Cavanaugh notes:

Key to this move is the contention that the church's business is religion. Religion must appear, therefore, not as what the church is left with once it has been stripped of earthly relevance, but as the timeless and essential human endeavor to which the church's pursuits should always have been confined. . . . In the wake of the Reformation, princes and kings tended to claim authority over the church in their realms, as in Luther's Germany and Henry VIII's England. . . . The new conception of religion helped to facilitate the shift to state dominance over the church by distinguishing inward religion from the bodily disciplines of the state.

Cavanaugh notes that for Enlightenment figures like Jean-Jacques Rousseau, who dismissed natural law, "civic religion" as in democratic regimes "is a new creation that confers sacred status on democratic institutions and symbols." He further shows that in their influential writings, Edward Gibbon and Voltaire claimed that the wars of religion in the sixteenth and seventeenth centuries were "the last gasp of medieval barbarism and fanaticism before the darkness was dispelled." Gibbon and Voltaire believed that after the Reformation divided Christendom along religious grounds, Protestants and Catholics began killing each other for more than a century, demonstrating the inherent danger of "public" religion.