With roughly three-in-ten (31 percent) Millennials now identifying as religiously unaffiliated the debate over why this generation is abandoning religion at an unprecedented rate has mostly centered around two explanations: Millennials are leaving because they do not like churches, but will eventually return as the churches change or as they change. Or alternatively, Millennials are leaving because they have fundamental problems with religion and subsequently few will return. Not surprisingly, many religious leaders tend to embrace the first explanation, while nonreligious people see greater merit in the second. Yet, both accounts have overlooked an important shift in religious affiliation: more Americans are being raised in nonreligious homes.
Beginning in the early 1990s, surveys began registering a modest uptick in the number of Americans reporting no formal religious affiliation. Recent surveys put the number at around one-in-five. As the ranks of the unaffiliated have grown so too has the number of Americans who were raised in nonreligious households, albeit at somewhat lower rates. In 1991, four percent of Americans were raised unaffiliated compared to eight percent in 2012. However, the generational differences are much starker. Thirteen percent of Millennials report that they were raised in a nonreligious household. In contrast, among Baby Boomers only five percent report being raised religiously unaffiliated.
An equally important development is the increasing resilience of nonreligious identity. In the United States, religious attachments have generally proven stronger than nonreligious attachments. This has been true for a couple reasons. First, regardless of their denomination or tradition, religious Americans tend to be embedded in religious networks of friends, family members, neighbors and leaders that reinforce religious beliefs and identity. Second, religious norms in society provide strong incentives to at least nominally affiliate. In contrast, religiously unaffiliated Americans represent an amalgam of atheists, agnostics, seculars and unattached believers. They tend to be more isolated from social networks that could reinforce their views--in fact the unaffiliated tend to be less civically and socially engaged than religious Americans. They are also less able to rely on established institutions to facilitate the maintenance of religious beliefs and commitments. Subsequently, Americans who were raised without religion in the past were not likely to stay that way. In the 1970s, only about one-third (34 percent) of Americans who were raised in unaffiliated households reported that they remained unaffiliated as adults.
However, there are signs that nonreligious identity is proving more durable, the result of increasing religious diversity, shifting marriage patterns and growing acceptance of nonreligious people. By the 1990s, the majority of Americans who were raised unaffiliated remained that way as adults. In the decade that followed, commitment among the religiously unaffiliated approached that of members of established religions. In 2012, more than 6-in-10 (61 percent) Americans raised unaffiliated were still without religion in adulthood. In comparison, two-thirds (66 percent) of Catholic adolescents remained Catholic as adults during this same time period.
Previous research has shown that marriage often serves to re-engage the religiously unaffiliated, particularly for men who tend to disaffiliate in higher numbers. But here, too, there is evidence that an institution, which previously reinforced religious identity, may now serve to reinforce secular beliefs. In the 1970s only 37 percent of unaffiliated Americans who were married had unaffiliated spouses. By 2010, a majority (54 percent) of unaffiliated Americans who were married reported that their spouse was also unaffiliated. That's still lower than the rate of religious homogamy among Catholics (76 percent), and Protestants (84 percent), but a dramatic increase all the same. Nonreligious Americans also are using religious identity as an important metric in selecting a partner. When picking a potential mate, nonreligious online daters are demonstrating a strong preference for those with similar religious beliefs.
The increasing number of Americans raised in nonreligious homes presents a significant challenge to churches. Instead of luring back those who were once part of a religious community, they now face the prospect of trying to attract those with no formative religious experiences to draw on. Moreover, Americans with no formative religious experience often have very different expectations and attitudes about religion that are drawn not from personal experience in church, but from the views of friends, family, and also popular culture.