Despite its conventional religious trappings, his education was leading him steadily away from the Church. But then, at the age of eighteen, while reading George MacDonald’s Phantastes (1858), the feeling recurred and this time it stayed. “I did not yet know (and I was long in learning) the name of the new quality, the bright shadow, that rested on [this book]. I do now. It was Holiness. . . . It was as though the voice which had called to me from the world’s end were now speaking at my side.” From that moment on, Lewis began to recover his faith, and the experience became the emotional foundation for his lifetime of Christian assurance. Lewis is clearly the odd one out in twentieth-century British history—one of very few figures of literary eminence to assert the compatibility of happiness and faith and to write about it at length.

In our own time, the British secularist tradition has found new champions, none more outspoken than Christopher Hitchens and Richard Dawkins, both of whom might reasonably be described as antireligious fanatics. Hitchens became an American citizen a few years ago, but the tone and mood of his God is Not Great (2007) indicate his continuing debts to his British upbringing. Where most Americans in public life make a sharp distinction between Islam as one of the “religions of peace” on the one hand and radical Islamism on the other, for example, Hitchens declines to do so. Instead, he declares about Islam, as about all other faiths: “Religion poisons everything.” Dawkins’s The God Delusion (2006), as its title suggests, regards religious people simply as lunatics. Both authors agree: religion is a source of misery, folly and untruth; happiness comes from getting rid of it.

IT WOULD be an overstatement to claim that happiness and faith are synonyms in America and antitheses in Britain, but the striking divergence of the two nations’ experiences makes it at least a powerful tendency. The political results of this contrast are profound.

Many burning issues in American politics, including school prayer, abortion, gay marriage, religious tax exemption and government aid to religious schools, seem baffling to British observers, where the necessary religiously motivated constituency is absent. Tiny handfuls of British Catholics and evangelicals do feel strongly, especially on the abortion issue, but their voices can scarcely be detected in a political culture that is overwhelmingly, and explicitly, secular. Where American candidates make a point of being seen and photographed going to church, British candidates and officeholders do it furtively if they do it at all. Tony Blair only went public about his conversion to Catholicism after leaving office in 2007; he knew it would have caused trouble during his premiership.

More striking still is the intensification of religion in American politics since the late 1970s. Evangelicals had largely withdrawn from politics after the fiasco of the Scopes Monkey Trial in 1925, when a high school teacher was found guilty of violating state law by teaching evolution. The state and its fundamentalist supporters endured ridicule from H. L. Mencken and the American mainstream media. Evangelical political activism reappeared with the creation of the Moral Majority during the Carter years. The theologian Francis Schaeffer regarded feminism, abortion, gay rights, evolutionary teaching and the breakdown of conventional family roles as threats to America’s Christian foundations. Jerry Falwell, Pat Robertson and other ministers tried to bring Schaeffer’s insights to bear in political life. Nonevangelicals like the Catholic convert Richard John Neuhaus joined in during the 1980s with warnings about the dangers of a “naked public square” swept clean of religious influences. Since then, the Christian Coalition and other groups of religious activists have vitally affected election outcomes, and given warning to candidates that they must show an increased respect for Judeo-Christian faith communities. If the “mosque at ground zero” doesn’t get built, it will be due largely to their influence.

Meanwhile, the puzzle of happiness remains unresolved. Mill was surely right in saying that happiness is impossible to measure and that it is impossible to aim for directly; happiness comes rather from other accomplishments and has to be attained indirectly. For each person it has its own character, meaning and significance. Despite all the polemics, it is as impossible now as it was in Thomas Jefferson and Tom Paine’s day to say whether religion does or does not lead to happiness, just as it is impossible to know whether God regards our pursuit of it as an inalienable right.

Patrick Allitt is the Cahoon Family Professor of American History at Emory University.