The marriage rate in the United States has consistently declined in the past 50 years while the percentage of children growing up with one parent has increased. If this doesn’t seem alarming to many of us today, it’s because we have a very different idea of marriage than the one that existed in the past. Until recently, marriage has been regarded as the means for starting a family and raising children. A decline in marriage means a decline in the only institution that can raise a new generation of people and ensure that they have the personal qualities and support necessary to succeed and be good individuals.

Whereas some traditionalists point to the expansion of marriage to same-sex couples as the cause of its degradation, other social attitudes and policies have had a far greater negative impact. On the one hand, those who consider the debate over gay marriage “settled” have probably not given much thought to what marriage actually is. But those who think gay marriage weakens the traditional family have become distracted from the greater marriage crisis—that of the high rate of divorce and single-parent households. While we’ve been focusing on the tiny percentage of Americans who would directly benefit from legal gay marriage, we’ve turned our backs on the most common household configuration. It’s in bad shape.

The nuclear family was a hallmark of American society since colonial times. In America there existed a kind of geographic mobility and freedom that was unrivalled anywhere else, and it allowed a break with the traditional norms of aristocratic Europe. This change constituted a redefining of marriage. It was no longer about “the uniting of goods,” as Tocqueville wrote, but rather “the similarity of tastes and ideas that brings man and women together . . . and fixes them beside one another.” In short, it was about the people.

For a long time, marriage being “about the people” meant that it was a route to the greatest and most respected joy in life: raising children. It also involved a sense of obligation. As Mary Beth Norton writes in Liberty’s Daughters, women in the early American republic had the esteemed, if confining, role of raising and educating the next generation of citizens. As long as a thriving family remained the ultimate American goal, personal happiness and the good of society enjoyed a close bond.

Since the 1960s government policies and social attitudes—especially radical individualism—have begun to marginalize the role of the family not only as the foundation of a good life, but also as the central unit of society. The expansion of no-fault divorce in several states has made it easier for men and women to leave their families, while also making marriage a less serious decision than it used to be. “Til death do us part” is an absurdity when you consider the number of marriages that end when the partners get bored with each other.

Meanwhile, federal welfare programs have encouraged absentee fathers by providing greater benefits to single-mother households. Progressives want to replace the family with the state, but don’t realize the consequences of doing so. They’re under the impression that there’s only one good way to raise children, and that we can’t just allow any average American to take on that responsibility. There’s no better example of this than Barack Obama’s “Life of Julia” online campaign advertisement, which tries to portray the government as a legitimate replacement for a family.

But the most significant cause of the marriage crisis is also the hardest to see. We don’t think of marriage in the same way anymore because we can’t conceive of a higher purpose than our own personal satisfaction. In this light, marriage isn’t about fidelity or obligation or raising good children. It’s about me. Who are we to judge people who rushed into bad marriages? It’s their decision, their prerogative, their consequences. But we know that’s an oversimplification.

The marriage crisis can’t be fixed by laws. We need to have the confidence to not only believe in social values, but to promote them. The process is uncomfortable: it involves judging people, stigmatizing certain behaviors, and being able to adequately defend values in terms of both morals and practicality. If we’re serious about marriage as a positive force in society we need to be concerned about the trend of diluting the institution into a temporary arrangement for personal interest. The greatest threat to marriage right now isn’t its expansion to same-sex couples, but the apathy toward marital obligations and a lack of regard for the importance of the family.