American Taliban John Walker Lindh has rightly become a symbol in America's ongoing culture wars.

Why? Because his case raises a crucial question: Is American culture capable of reproducing itself? Are we raising children who can preserve our society for future generations? Taliban John suggests the possibility that some of our children won't even stay on the right side of an overt military conflict.

Does a nation of individualists have reason to care whether society survives? Before I had children, I didn't have a very good answer to that question. I would have said that I prefer that it survive, because on the whole it is a good society. Then, too, a society that falls apart the day after I die would probably not be much fun to live in during the last years of my life. But if asked whether that preference imposed any obligation on me for actual action, I would have been hard pressed to figure it out.

Many people, in fact, reply with something like this: “I owe nothing to anyone. I don't have to have children at all. If I choose to have children, how I raise them is up to me. What do I care if society doesn't last beyond my own lifetime?”

After having children, I realize that this question is ill-framed. The more important question is this: Is it in the interest of a free society to allow people greater and greater liberty in a wider number of areas, at ever-earlier ages? Posed this way, it is easy to see that even the most free society must impose some limits on the behavior of its individuals. We can't turn a blind eye to stealing and murder. Economists know that we need reasonable compliance with reasonable laws of property and contract for the smooth operation of the market. We don't have to tolerate the “preferences” of con artists and gang members for their “lifestyle.”

So do these necessary restrictions on people's behavior extend to how we raise our children? A couple of recent books say Yes. Kay Hymowitz, in Ready or Not: Why Treating Children as Small Adults Threatens Their Future and Ours, argues that allowing children a greater range of choices at earlier and earlier ages actually undermines their ultimate maturity and autonomy. Children are not ready to make certain kinds of decisions. They need adult guidance and protection. Hymowitz points out that the children who receive the least adult input into the formation of their values are the most vulnerable to far less benign influences outside the family. She mentions influences like advertising and peer pressure, to which we can now add, thanks to John Walker's case, militant Islam.

In my own book Love and Economics: Why the Laissez-Faire Family Doesn't Work, I show that no one is born with a well-formed conscience. The groundwork for the development of the conscience is laid during the first two years of life, through the attachment between the infant and his mother. If that foundation is not laid during the pre-verbal, pre-cognitive period of the infant's life, it will be very difficult to install a conscience based on purely rational, abstract considerations of justice.

What do I care if society doesn't last beyond my own lifetime?

Children have to be raised with enough attachment to the rest of the human race that they will restrain themselves in the face of temptations to do wrong. Or, in John Walker Lindh's case, children need to have enough attachment to their own society to refrain from taking up arms against it.

Don't get me wrong. No one is talking about government monitoring bedtimes and breakfast menus. Instead, I am talking about creating a culture of reasonable conduct for parents and children alike. I am not advocating a culture of compulsion, but a culture of raised eyebrows, social ostracism and dirty looks.

Legal enforcement of social norms by the state is, in many cases, a substitute for informal enforcement of those norms by ordinary people. The state is not competent to enforce family behavior in very much detail. We leave to state enforcement the large, seriously dangerous activities that the private sector can't handle. We can't have private enforcement of laws against treason or espionage. But we have to count on mothers and fathers to instill a basic sense of right and wrong. Only parents can create the basic attachment to society and its norms that will allow the society to flourish with a minimum of state coercion.

Look at it this way. Someone in Marin County could have said some pointed and even downright judgmental things to Mr. Lindh and Ms. Walker when they paid their son's airfare to Yemen. Someone could have suggested to Mr. Lindh that leaving his wife to go live in a homosexual relationship might have a deleterious impact on his son. Someone could have mentioned to Ms. Walker that she could provide her son with a more solid structure as a practicing Catholic than as a dilettante in eastern religions. If some combination of those informal, albeit unpleasant, encounters had taken place, maybe they would be watching their son graduate from college instead of fearing for his life in a federal courtroom.

The parents and the culture around them failed to attach this boy to his society through affection. Now the state has to do that job with force. That is why a free society needs a robust culture of right and wrong.

Jennifer Roback Morse is a research fellow at Stanford University's Hoover Institution.