Marriage is in trouble in Middle America. High rates of divorce, nonmarital childbearing and single parenthood were once problems primarily concentrated in poor communities. Now, the American retreat from marriage is moving into the heart of the social order: the middle class.

This retreat from marriage imperils the social and emotional welfare of children. It also threatens the American Dream, insofar as adults who do not get and stay married are less likely to strive, to succeed and to save for the future.

This stark assessment emerges from a new report, When Marriage Disappears: The Retreat from Marriage in Middle America, sponsored by the National Marriage Project at the University of Virginia and the Center for Marriage and Families at the New York-based Institute for American Values.

The report explores marriage trends among three segments of American society: high school dropouts (12 percent of the adult population), those with high school diplomas who didn't go on to college (58 percent of adults) and college-educated men and women (30 percent).    

These segments of society reveal sharp differences in the marriage experience, and expectations for it. But the most striking finding is this: Marriage has declined most precipitously among the "moderately educated"—that is, those with a high school education, who make up the biggest number of adults.

The breakdown of marriage and family has afflicted the poorest Americans for more than a generation. What is happening today is a widening gulf between the middle class, where a sharp decline in marriage is at work, and the most educated and affluent Americans, where marriage indicators are either stable or improving.

Many of us need to adjust our thinking to recognize that the greatest threat to marriage may be the shrinking commitment of couples in middle class havens such as Wichita, Kansas, or Greenfield, Mass., not in rich enclaves such as Grosse Pointe, Mich., or blighted neighborhoods such as East St. Louis. Not surprisingly, the dangers posed by a class-based disappearance of marriage also have implications for the decline of religious belief and worship, as well as beliefs about the moral or cultural underpinnings of family life.         

Just as getting married changes individuals, failing to marry delays or defers personal maturity. For earlier generations, marriage functioned as a gateway to acceptance of adult responsibilities and habits—including attendance of religious services—that reinforce those responsibilities.  Narrowing or closing that gateway has profound effects.

Take this example: The divorce rate, as measured within 10 years of marriage, fell from 15 percent to 11 percent among college-educated adults between the early 1970s and late 1990s. But the divorce rate rose from 36 percent to 37 percent in the same period among those with a high school education, putting it slightly higher than the 36 percent rate among the least-educated Americans.

Trends in marital happiness are similar. From the 1970s until recent years, the number of spouses between ages 18 and 60 who reported being "very happy" in marriage dropped from 68 percent to 57 percent among moderately educated Americans. Those saying they were "very happy" dipped from 59 percent to 52 percent among the least-educated, while there was no drop in marital happiness among the highly educated.    

More starkly, the proportion of moderately educated adults who are in their first marriages declined from 73 percent in the 1970s to 45 percent in the 2000s. For this education and income range, marriage is now a minority experience.

Children are the first to feel the effects of such changes in the behavior of adults. In 2008, out-of-wedlock births in the United States surpassed the 40 percent mark for the first time—meaning that of 4.25 million babies, some 1.7 million were born to unmarried mothers.

Among moderately educated Americans, the out-of-wedlock birth rate hit 44 percent, up from 13 percent as recently as 1982.  Again, Middle America moved closer in behavioral norms to the poorest Americans, even as more educated and wealthier Americans are embracing a marriage mindset.

Reasons vary for this decline in Middle America's experience and expression of marriage, but they include a decline in marriage-friendly values and a disturbing decoupling from religious attachments. Although their aspirations for a traditional marriage remain high, these Americans—and their children—appear to be turning away from a marriage mindset.

Only one in four moderately educated Americans believes premarital sex is always wrong. Among adolescents whose mothers have only a high school education, only six in 10 would be embarrassed to give birth outside marriage. Having multiple sex partners also is on the rise for this group.

None of these changes, of course, occurred in a vacuum. They correlate with evidence of a spiritual void. Since the 1970s, moderately educated Americans show the largest decline—fully 30 percent—in weekly attendance of religious services. The edge they once enjoyed in this regard has disappeared; Americans with four-year college degrees now attend church more regularly.

Marriage in Middle America is poised on a knife edge. The majority could go one way or the other. Faith, however, is constantly at odds with fatalism—the idea that historical or cultural trends are determined or irreversible.  Faith is also in tension with materialism, the notion that human existence is no more than the ceaseless acquisition of consumer goods or sensory gratifications.

The resurgence of belief in marriage and support for divorce reform among better-off Americans is therefore encouraging.  Still, the possibility that a separate and unequal marriage regime is rising in America is alarming.    

We cannot afford to be a nation where marriage is a luxury good, just another hallmark of a patrician lifestyle. Renewing the fortunes of marriage in Middle America, and closing the marriage gap between middle and upscale Americans, deserves to be a national priority.

In fact, if we were serious about the state of marriage and what it is likely to take to rebuild it, we would think of something on the scale of a Marshall Plan for marriage. In this case, though, such a plan would work in reverse to lower social costs and ease government investment in the safety net.

If no simple prescription exists, many medicines must be tried. Remedies include extending tax breaks to alleviate marriage penalties; reforming welfare programs in a way that neutralizes or reverses incentives for cohabitation; strengthening employment prospects for those with a high school education; and transforming the culture to restore the desirability of marriage and parenthood for all Americans.    

We also should do more to boost religious and civic institutions that provide our genuine relationships and bring meaning and purpose to our lives. 

As we work to restore the status marriage confers, we also ought to act quickly to communicate the benefits it offers. We should aggressively pursue improved marriage education programs. Robert Rector, an authority on poverty and welfare at The Heritage Foundation, points out that marriage education can meet students and young adults where they are—in schools and in low-income neighborhoods—and reduce future burdens on taxpayers.

In a speech to the National Association of Evangelicals in 1998, theologian Harold O.J. Brown pronounced his concern about the decline of marriage, which he rightly called "the most significant of all formal human covenants."   By the time of Dr. Brown's death in 2007, the tendrils of marital dissolution had insinuated themselves into the nation's core communities.

Across the political spectrum, renewed urgency about getting America's economic house in order proved an irresistible force in the 2010 elections.  But that house did not enter disarray overnight, and neither did the married households of Middle America.

In Congress and state legislatures alike, lawmakers who want to repair our economic house must not restrict themselves to the task of restoring material prosperity.  The strength of the marriage covenant needs their urgent attention as well.

W. Bradford Wilcox is director of the National Marriage Project at the University of Virginia. Chuck Donovan is senior research fellow in the Richard and Helen DeVos Center for Religion and Civil Society at The Heritage Foundation.