Are Americans Becoming as Godless as Europeans?

This article first appeared on the London School of Economics site.

The religiosity of the United States has impressed observers since the early 19th century, and American levels of religious involvement remain strikingly high compared to those in virtually all highly developed countries.

The US is often taken to be a decisive counter-example to the idea that modernization tends to undermine religious belief and activity (what's known as the "secularization thesis").

It's become clear, though, that American religiosity has been declining for decades. What's more, this change has been produced by the generational patterns underlying religious decline elsewhere in the West: each successive birth cohort is less religious than the preceding one. Taken together, these two facts mean that trends in religiosity are remarkably similar across the western world.

Religious affiliation, church attendance and belief in God have all fallen in the US. None of these declines is happening fast, but the signs are now unmistakable.

To take religious belief as an example, only 45 percent of young adults aged 18-30 have no doubt about God's existence, compared with 68 percent of people aged 65 and over. The overall level of belief is being eroded as people born early in the 20th century are replaced by members of subsequent generations with weaker religious convictions.

Children are raised by parents who are less religious than their parents were, and the culture is reshaped with the passing of each generation.

These declines in traditional religiosity aren't offset by increasing vitality elsewhere. It's true that the "spiritual but not religious" phenomenon has expanded in recent years. This diffuse spirituality may provide a growing market for certain kinds of religious products, such as self-help books with spiritual themes, but it isn't offsetting religious decline, re-energizing existing religious institutions, or providing a foundation for new forms of religious collective action.

It's not just the fact of religious decline that makes the United States similar to Great Britain, Australia, New Zealand, Canada, or most of Europe. It's also the way that secularization has occurred mainly, and in some cases entirely, because each successive generation is slightly less religious than the one before.

Figure 1 shows a good example: religious affiliation in Great Britain has declined from one decade of birth to the next for years of birth going back to the beginning of the 20th century. There is remarkable stability over the adult life course for all generations.

Individuals might become more or less religious, but within generations these gains and losses largely balance out. That means that decline isn't a matter of people losing their religion in adult life; it's about people being less religious than their parents and grandparents.

Figure 1 – Religious affiliation by decade of birth, Great Britain, 1983-2013

Source: British Social Attitudes survey 1983-2013 Note: Includes white respondents aged 20-84. Graph shows three-survey moving average.

The basic results are the same whether we examine religious affiliation, attendance, or belief in God. It's well known that an increasing proportion of Americans say that they have no religion. That's a generational effect, and churchgoing tells the same story.

Figure 2 shows monthly attendance at religious services in the United States; the pattern is very similar to what we see in Figure 1. Gentle decline within birth cohorts during the 1970s was followed by rising participation in the 1980s, after which within-generation change is very minor.

Churchgoing decline in the United States is driven by the same cohort replacement mechanism that drives religious change elsewhere in the West.

Figure 2 – Attendance monthly or more often by decade of birth, United States, 1973-2014

Source: General Social Survey, 1973-2014. Note: Includes respondents aged 20-84 born in the US. Graph shows three-survey moving average. To avoid overstating religious decline, the unusually religious 1972 GSS sample has been excluded.

Religious decline is America isn't new: it seems to have begun with people born early in the 20th century. At least since then, strong religious affiliation, church attendance and firm belief in God have all fallen from one birth cohort to the next.

None of these declines is happening fast, and levels of religious involvement in the United States remain high by world standards. But the signs of both aggregate decline and generational differences are now unmistakable.

Most research that compares American religion with religion elsewhere emphasizes the high levels of participation in the United States, and treats those high levels as strong evidence that America is exceptional.

If we look at the trends, though, it appears that the US isn't a counter-example to the idea that modernization causes problems for religion. On the contrary, religious change in the United States is very similar to what we see elsewhere: long-term decline produced mainly by generational replacement.

This process operates slowly, and it can be counteracted in the short term by short-lived revivals, but it is very difficult to reverse.

An obvious agenda for future research is to try to understand better the causal mechanisms that lie behind these cohort differences. What social and cultural changes make each generation slightly less religious than the previous one? What is the relative importance of changes in geographical mobility, family structure, education, technology, economic conditions, and other factors?

We haven't tried to identify all the causal forces at work, but we hope future research will make progress on this agenda.

We should ask, "Why did secularization take hold in the US when it did?" rather than "Why is secularization not occurring in the United States?" It may be that some of the explanatory factors invoked in answers to the traditional question – such as church-state separation or immigration history – help to explain why religious decline started later and is occurring more slowly in the US than in some other places.

Nevertheless, over the long run, religious involvement is being undermined by the same forces that have operated in the rest of the industrial and post-industrial world.

The big question is whether or not modernity, sooner or later, brings secularization. Many scholars have been saying "No," citing America's apparently exceptional status. The question is still open, but since it is no longer clear that the US is on a qualitatively different religious trajectory, assertions that the secularization thesis does not apply outside of Europe, Canada and Australia are unwarranted.

It now seems that the classic question – Does modernization undermine religion? – has been prematurely answered, "Not in general." That answer needs to be reconsidered.

David Voas is Professor and Head of the Department of Social Science at UCL Institute of Education, University College London. His research focuses on religious change, and on beliefs, values and attitudes more generally, in developed societies. He is on the leadership group of the European Values Study and is co-director of British Religion in Numbers.

Mark Chaves is Professor of Sociology, Religious Studies and Divinity at Duke University. He directs the National Congregations Study, a wide-ranging survey of a nationally representative sample of religious congregations conducted in 1998, 2006 and 2012. Much of his research focuses on the social organization of religion. His most recent book is American Religion: Contemporary Trends (Princeton University Press, 2011).

This article is based on the paper, Is the United States a Counterexample to the Secularization Thesis? in the American Journal of Sociology.

This article gives the views of the authors and not the position of USAPP – American Politics and Policy, nor the London School of Economics.