From the day the Pilgrims stepped off the Mayflower, religion has played a prominent role in American public life. The faithful have been vital participants in nearly every major social movement in U.S. history, progressive as well as conservative. Still, the close intertwining of religion and politics in the last 40 years is unusual, especially in the degree of the politicization of religion itself. Indeed, religion's influence on U.S. politics has hit a high-water mark, especially on the right. Yet at the same time, its role in Americans' personal lives is ebbing. As religion and politics have become entangled, many Americans, especially younger ones, have pulled away from religion. And that correlation turns out to be causal, not coincidental.
It is no surprise that religion and politics should be connected to some degree in a highly religious and democratic nation. In the nineteenth century, U.S. political parties were divided along sectarian lines: pietistic versus liturgical, low church versus high church, Protestant versus Catholic. But whereas the past saw partisans of different religions (often with an ethnic tinge) face off in the political arena, today partisan divisions are not defined by denomination; rather, they pit religiously devout conservatives against secular progressives. Moreover, to a degree not seen since at least the 1850s (and perhaps not even then), religious mobilization is now tied directly to party politics.
In fact, over the last 20 years, church attendance has become the main dividing line between Republican and Democratic voters. (African Americans are a sharp, but singular, exception; although most Democratic voters are now secular, African Americans, the most loyal Democrats, are also the most religious group in the United States.) The so-called God gap, between churchgoing Republicans and secular white Democrats, rose sharply throughout the 1990s and early years of this century. Before the 2008 presidential election, one team of consultants even specialized in teaching Democratic candidates how to "do God," so they could eat into the Republicans' support among religious Americans. Yet in 2008, the God gap remained as wide as ever: according to data we collected, among whites, 67 percent of weekly churchgoers voted for Senator John McCain, as compared with 26 percent of those who never attended church.
The connection between religiosity and political conservatism has become so deeply embedded in contemporary U.S. culture that it is startling to recall just how new the alignment is. In the 1960s, churchgoers were actually more likely than nonchurchgoers to be Democrats. Into the 1980s, there were still plenty of progressives in the pews on Sunday morning and plenty of conservatives who stayed home. The rather sudden shift since then has, and will have, both short-term and long-term implications for both politics and religion. For now, Republicans must seek to appease their fervently religious base without alienating a general electorate that increasingly finds the mixture of religion and politics distasteful. In the long run, the trend could undermine the historic role of religion in the United States, as younger generations reject organized religion itself. The country has arrived at today's close nexus between religion and partisanship only recently, and understanding how it got there-and how the role of religion in the United States has changed in recent decades-will help explain where it might be headed.
In the beginning
To get a better sense of how novel the present political-religious landscape is, we must go back to the 1950s.That decade was highly religious; indeed, some historians argue that it was the most religious in all of American history. Of course, there are many ways to gauge national trends in religiosity, but for decades, one Gallup poll question, "Is religion's influence on American life increasing or decreasing?" has proved a finely tuned seismometer of religious tremors. …