Americans are having a debate about marriage that's too important to be stopped by the United States Supreme Court.

A proper understanding of marriage is critical to the wellbeing of future generations of children. With good reason, 41 states define marriage as the union of one man and one woman.

Marriage exists to bring together a man and woman as husband and wife – and to be mother and father to the children that their union may produce.

Much of the rhetoric on the side of same-sex marriage tends to blur this understanding. Even so, the institution of marriage, which predates government, is based on the truth that man and woman are different.

It's based on the biological fact that bringing forth new life depends on a man and a woman. And it's based on the social reality that all children need a mom and dad.

On March 26 and 27, the Supreme Court will hear challenges to state and federal laws defining marriage as the union of one man and one woman.

In the first case, the nine justices will hear arguments on California's Proposition 8, the voter-approved amendment to the state constitution affirming that marriage is between a man and a woman. In the second case, the court will decide a challenge to the federal Defense of Marriage Act (DOMA), which was passed overwhelmingly by Congress in 1996 and signed into law by President Bill Clinton.

Congress recognized the welfare of children as government's reason for supporting marriage, singling it out as a factor in enacting the law. In Congress' own words:

Were it not for the possibility of begetting children inherent in heterosexual unions, society would have no particular interest in encouraging citizens to come together in a committed relationship. But because America, like nearly every known human society, is concerned about its children, our government has a special obligation to ensure that we preserve and protect the institution of marriage.

Family is the foundation of society and marriage is the foundation of the family. You don't have to believe that God designed marriage to understand this truth.

Government recognizes marriage to encourage men and women to commit to each other and to take responsibility for their children. Congress simply re-acknowledged this basic truth more than 16 years ago in passing DOMA.

What's more, common sense tells Americans that a strong marriage culture limits the size and scope of government. Decades of social science research bears this out, showing that marriage is the best place for children to thrive.

Redefining marriage to include same-sex relationships would sever the link between marriage and the bearing and raising of children. It would become impossible for government to promote the ideal that mothers and fathers are essential when same-sex marriage communicates that both are optional. And government is certain to continue to grow to address the negative results such as more poverty, drug abuse, and crime and lower education levels.

Finally, same-sex marriage is a sure threat to religious liberty. Faith-based adoption agencies in Washington, D.C., and Massachusetts already have been forced out of business for holding to deeply held religious beliefs and declining to arrange adoptions by same-sex couples.

No matter the assurances, it's easy to foresee how redefining marriage would lead to the slow and subtle erosion of our first freedom.

Americans are free to love and live with whomever they choose, but no one -- not even the Supreme Court -- has the right to redefine marriage for us all.

Yes, we are in the midst of a contentious debate about marriage. In fact, the debate is really just beginning, as Americans look beyond the attractive "marriage equality" slogan.

The debate is often uncomfortable. It elicits strong opinions from both sides. The Heritage Foundation and allied groups have produced a new booklet to help Americans engage in this conversation.

This debate is integral to the democratic process, a process that shouldn't be taken away by the Supreme Court. It's important, for the sake of generations yet to come, for the debate on marriage in America to continue.

-Andrew T. Walker is a policy analyst in the DeVos Center for Religion and Civil Society at The Heritage Foundation.