"Why?" she protested. She wanted to watch the birds skip across the front lawn.

"Because you have to be next to Mommy at all times." That was the easy answer. The real one was more complex: Because the world is a dangerous place? Because I don't know every person who walks down our suburban street? Because if I let you out of my sight for 15 seconds, something terrible could happen, and it would be all my fault?

Last week, Lenore Skenazy set me straight by asking me a question: How long would you have to leave your kid outside alone for it to be statistically likely that she gets kidnapped?

Answer: 750,000 years.

Skenazy, a syndicated columnist from New York, has done her homework - and, in doing so, has become something of a patron saint of the parental reality check. A little more than a year ago, she wrote a column in the New York Sun headlined “Why I Let My 9-Year-Old Ride the Subway Alone.’’ Her son was a Manhattanite who had been begging for the chance to ride the train by himself. He made it home safely, Skenazy wrote. Some readers cheered. Others wanted to report her to child welfare.

But Skenazy held firm and expanded her idea. Now she has a blog and a book dedicated to the philosophy she calls “Free Range Kids.’’ She collects outrageous stories of overprotection: a Texas school system that runs background checks on parents who want to volunteer, Connecticut parents who drive their kids from the garage to the foot of the driveway to catch the school bus. Through it all, she preaches common sense. A sample post:

“From the SafeKids.org page of advice to parents of kids ages 5-9:

‘Never leave your child alone in a car, even for a minute’

A minute?

Lenore’’

It’s all she needs to say. Scan her blog for a while, and the world seems a little less dangerous and a lot more absurd.

It’s tough to be a sane and sensible parent in an age of fear and fear mongering, of wall-to-wall TV news coverage of abducted children and the notion that, as Skenazy says, “everyone is a pedophile until proven otherwise.’’

The fears start with pregnancy, a blur of warnings about what to eat, what not to drink, how to sleep. Before my son was born last summer, I ate voluminously at a barbecue, wound up with a stomachache, and imagined the worst: What if I had unwittingly eaten feta cheese? So I called my obstetrician’s office to report that I might have Listeria poisoning.

The on-call doctor laughed. When your doctor laughs at you, it’s both a good sign and a bad one.

“You ate too much,’’ she said. “Listeria poisoning is incredibly rare.’’

“Then why do we get so many dire warnings about it?’’

She didn’t have an answer, but I think I do now: fear of liability. When I did a Google search for “Listeria poisoning’’ the other day, the first site that came up was a fact sheet on Listeriosis . . . from a law firm that specializes in food poisoning cases.

That’s Skenazy’s argument: Follow the money, and you’ll get a firmer sense of how to manage your risks. She jokes about the Kiddie Safety Industrial Complex, which convinces us that blankets are inherently unsafe and produces baby knee pads to protect from the dangers of crawling.

As kids get older, the worries change. Fear of cheese and blankets evolves into fear of strangers, fear of the park, fear of a child left alone for an instant outdoors. Here’s where good intentions get twisted, Skenazy says: By sequestering kids from the world, we’re thwarting their ability to fend for themselves. Experts in missing children have told her that the kids who escape from dangerous situations are the ones who are confident - and who have experience fending for themselves in the world.

Besides, she says, it doesn’t do our kids good to teach them that the world is nefarious all the time. A few strangers out there are dangerous, to be sure. Our kids should know not to get into cars with them, the old-school stuff. But most of the ones who see a cute girl on a porch on a sunny morning will give a friendly wave and continue on their way.

Joanna Weiss can be reached at weiss@globe.com.