A missing-person sign for Leiby Kletzky posted in the Orthodox Jewish section of Borough Park in New York. Leiby was found dead. (Shannon Stapleton/Reuters)

I wish I could publish it intact and without preamble today. But in the days between the writing and the publishing, the context for this subject changed tragically. The post had been about the lost art of walking to school, written three days before an 8-year-old in Brooklyn tried to walk home for the first time from his summer camp.

I will not describe the details around the Leiby Kletzky killing, except to point out the obvious facts that it shattered a community and terrified every parent who heard about it.

Suffice it to say, it’s a a bad time to lecture parents about the importance of fostering the independence that comes for a child when he is encouraged to walk to school.

It is not, though, a bad time to consider the subject. It might be the best time. What happened this week is one of the biggest reasons why so few kids walk to school now, only 16 percent according to a 2008 study for Journal of Physical Activity and Health (down from 42 percent in 1969). Just as a generation of parents identified with the parents of Etan Patz 32 years ago, we will identify with the Kletzky family. We will now be much quicker to question what and who lurks outside.

In theory, walking to school is a wonderful habit. It can teach children independence, introduce them to their neighborhoods and encourage physical activity. It’s better for the environment, eases traffic and is just generally the most fun option.

Many of us parents don’t allow it, citing the challenges of logistics and distance. What we talk about less often is our fear. Maybe that’s the heart of it.

The study I originally wanted to write about found that although the barriers our families face in allowing our children to walk to school are real, we are the ones who most often introduce them. The more options we have and the more money we have, the less likely our kids are to walk.

Longitudinal Changes in Active Transportation to School in Canadian Youth Aged 6 Through 16 Years” will be published in next month’s issue of Pediatrics and was published this month online. It’s the first look at how schoolchildren have gotten to school over time.

By studying a group of Canadian children through the years, Roman Pabayo, who conducted the research as part of his PhD thesis at the University of Montreal and is soon to become a post-doctoral fellow at the Harvard School of Public Health, found that those with the fewest options for transportation, in lower-income and single-parent households, walked the most.

Pabayo speculated that since those families had fewer resources, they were less likely to have a second car or non-working parent to shuttle a child to school. They were also less likely to send children to a distant private school. In other words, necessity dictated walking.

Also, he found that children in a home with an older sibling walked more. A trusted chaperone can change the equation.

Pabayo had hoped his findings would trigger a conversation in Canada, and its southern neighbor, about how to reintroduce walking to school as a childhood rite of passage.

“We’ve gotten so used to cars that it’s changed our perceptions of distance. We think a 20-minute walk is too far. Actually, it’s not far at all,” he told me before the Kletzky killing.

Who could know that a different news event would trigger a different sort of unspoken calculation for so many parents? “No way am I letting my child out there by himself,” many of us thought to ourselves.

Fear is certainly an understandable reaction. It is not a justified one. What happened this past week is the definition of anomaly. This case is exceedingly rare.

Separating out the facts from the feelings is a difficult thing to do. Very few of us were ready to breathe easy about sending our vulnerable children off by themselves no matter what statistical charts said about the unlikelihood of tragedy. We are far more anxious now.

The good news is we don’t have to be. Those children without a capable, reliable older sibling can be escorted when the neighborhood forms a “walking school bus.” That’s when designated parents walk with groups of children from home to school. With the benefit of safety, it allows kids to enjoy one of the joys of childhood. It’s an easy, affordable option.

A walking school bus is one of the good ideas that parents come up with when they stand back and think about what our modern fears have wrought. Solutions are usually out there. Sometimes all they take is a little cooperation and a lot of courage.