In other words, it is hard to imagine a plot to bring harm and unhappiness to human lives that can compare, in social and economic terms, to the marginalization of marriage.

Hold that thought as you consider another dimension to this picture. For most of the last century, we have been concerned about the alienation of the cultural and intellectual elites from the institution of marriage. Starting at least as far back as the 1920s, the most highly educated Americans moved away from commitment to marriage. In contrast, the middle class held tenaciously to marriage in both institutional and moral terms. Middle-class Americans and those even lower on the economic scales tended to get married, to stay married, and to have children only within the institution of marriage.

Yet, in a stunning reversal of these commitments, more educated and more wealthy Americans are now more likely to be married, to stay married, and to have children only within marriage. In one of the great tragic and unpredicted developments of our times, less educated Americans are now far less committed to marriage than in the recent past and even less committed to marriage than the educated elites.

As researchers now explain, the "moderately educated" (high school graduates who may have some college but no baccalaureate degree) are now increasingly alienated from marriage. This massive shift in moral and institutional commitment to marriage is a tragedy of epic proportions unfolding before our eyes, yet it is now well underway.

In When Marriage Disappears: The New Middle America, a top-notch research group provides ample documentation of this tragedy. Each year, the National Marriage Project at the University of Virginia and the Center for Marriage and Families at the Institute for American Values release a report entitled The State of Our Unions. This most recent report, released just this month, offers a devastating look at the marginalization of marriage among Americans who had formerly been marriage's staunchest defenders in both theory and practice. What happened?

America now faces a "marriage gap" that can only be described in stark terms. The moderately educated are now less likely to get married, to stay married, and to reserve children for marriage. These Americans are now less likely to form lasting marriages, while the more highly educated are now more likely to do so. For those moderately educated Americans who do marry, their marriages are now declining in measures of quality and stability. Divorce rates are now lower for the more highly educated and higher for the moderately educated. The moderately educated middle class is now "dramatically more likely than highly educated Americans to have children out of marriage."

Out of wedlock births for the highly educated now run at about 6 percent. Compare that to 44 percent for moderately educated mothers and 54 percent for those with the least education. The children of the more educated are now more likely to live with both biological parents than the children of the moderately educated middle class. As the researchers note, patterns that devastated minority and urban populations in recent decades have now spread to the suburbs and Middle America.

As W. Bradford Wilcox of the University of Virginia explains:

The numbers are clear. Wherever we look among the communities that make up the bedrock of the American middle class–whether small-town Maine, the working-class suburbs of southern Ohio, the farmlands of rural Arkansas, or the factory towns of North Carolina–the data tell the same story: Divorce is high, nonmarital childbearing is spreading, and marital bliss is in increasingly short supply.

Kay S. Hymowitz warned of this looming disaster in her 2006 book, Marriage and Caste in America: Separate and Unequal Families in a Post-Marital Age. Now, less than half a decade later, the alienation of the middle class from marriage is taking place before our eyes.

The researchers suggest that the great "change of heart" on marriage within the middle class can be traced to three developments. First, even though the moderately educated have traditionally been more conservative on moral issues related to marriage, they are now increasingly more permissive in terms of social and sexual morality. In a great and ironic turn, the more highly educated are moving into more conservative patterns, even as the great middle is turning more permissive.

Second, this new permissiveness means that these Americans are now more likely to be involved in behaviors "that endanger their prospects for marital success." These behaviors include multiple sexual partners and marital infidelity.

Third, moderately educated Americans are now significantly less likely to embrace the "values and virtues" that are required for marital success. The researchers point to temperance, delayed gratification, and educational aspiration as examples of these disappearing virtues. Marriage rests upon a moral foundation, and without these virtues (and others), marriage is exceedingly difficult to sustain.

Add to all this another ominous finding. Since 1970, moderately educated Americans have experienced the most significant drop in religious attendance. In the words of the report, "Over the last 40 years, then, Middle America has lost its religious edge over their more highly educated fellow citizens."

This finding is supported by data from churches and denominations. The decades of massive church growth in suburban America have given way to a much more complicated and difficult terrain - and the marginalization of marriage is tied to this phenomenon, as well.

In terms of any religious dimension, this is as far as When Marriage Disappears takes us. Christians, of course, will have much to add to this picture. We know that marriage, though central to human society, was not given to humanity for purely sociological reasons. Marriage was given to mankind by our Creator, who gifted us with this covenantal institution for our health, our happiness, and for human flourishing. Beyond this, believers know that marriage is given to us for our holiness, as well.

Thus, for reasons that include all that we can learn from this report, and for many more that we know from the Scriptures and Christian wisdom, Christians know that the marginalization of marriage can only lead to unhappiness, unhealthiness, and the unraveling of human relationships.

We have no choice but to look this documentation squarely in the face. Are we not watching marriage disappear for many before our eyes?

You can write Dr. Mohler at mail@albertmohler.com. Follow regular updates on Twitter at www.twitter.com/AlbertMohler.

----Dr. R. Albert Mohler, Jr., serves as president of The Southern Baptist Theological Seminary - the flagship school of the Southern Baptist Convention and one of the largest seminaries in the world.