Whose job is it to ensure people’s safety? How do I respond to a tough biker who’s aware that I strongly support helmet laws — not just for people on Harleys, but for kids on skateboards?

Fishing for today’s topic, I got a TiVo-type glimpse of the NBA Wunderkind LeBron James of the Cleveland Cavaliers as he got knocked down (and almost out) in a game against the Mavericks on Wednesday night, when the back of his head lost a battle with the hardwood floor. Does this mean I’d be in favor of helmets for basketball players as well? Perhaps.

But here’s how I zoomed in on this topic:

I was driving west on Mills Wednesday, alongside a woman in a large, old SUV with a child no older than 4, in the front seat. The child wasn’t buckled in; in fact, she was bouncing on the seat.

In avuncular fashion, I glanced over, got the mom’s attention and tugged at my own seat belt as a signal that she ought to have her kid belted in. Her reaction was the start of half a peace sign, the kind of gesture in which one holds up the three middle fingers and asks us to “read between the lines.”

She stopped short of delivering the digitus impudicus — possibly out of respect for her bouncing-around child, but by that time, the light had changed and she was on her way. I felt embarrassed, not because of her almost flipping me off, but because of my meddling. How did I acquire the temerity to try to influence someone else’s behavior?

Had we exchanged words and I’d said, “I suggest you buckle up your child,” I’m sure her response would have been, “Mind your own business.”

It is my business, but more about that later.

A couple of years ago, my wife and I were tooling along on North Seventh Street, heading toward town. We were behind an old van when we saw what we thought was a doll flying out the right side sliding door. In the same way that some people aim their cars at the one empty beer can tossed on the road, some base instinct tempted me to head toward this object.

But after flipping over a couple of times, the “doll” got up, dazed and started running toward the van she had just exited. As we were immediately behind them, I slammed on my brakes, blocking the street by parking at an angle, as someone in the inside lane did the same thing. All of the southbound traffic stopped.

The driver got out of the van in such a hurry that she forgot to apply the brakes. A couple of witnesses stopped the van from rolling as the mother tended to the child.

The mom clearly was in a panic, needing to explain not only what happened but why. “The kids were fighting in the back seat and the bigger one pushed her out.” She seemed more embarrassed that we’d be judgmental: our concern was with the child — Is she injured? Do we need to call an ambulance? The little girl never uttered a sound. No tears, no complaints, just a stoic look that we’ve all been told to observe during our first aid classes.

And we didn’t ask, though we were curious, whether any of the other kids in the van had been buckled. As she loaded her child into the van, she said she was taking the child to the emergency room. But she didn’t appear headed there at all. The emergency room then was on Eighth Street. Apparently the mom believed the child was all right.

It still amazes me, given the laws of physics, that a 35-pound body hitting the pavement at 30 mph is able to get up, shake it off and run toward the vehicle she’s just been ejected from. Anyone who’s ever wiped out on a bicycle, going as slow as 15, knows the pain that comes when flesh meets the asphalt.

Well, that was two or three years ago. I assume the child and her family are doing okay. At least they’re wiser now.

So, how do an unbelted child with a one-finger-salute-giving mother, or a kid that pops out of a van, or a macho man who lets his head serve as a helmet become my business?

That’s easy. People who take needless risks force the tightening of laws, the stiffening of fines and the raising of insurance rates that affect all of us.

These are some of the reasons you hear from people who fail to use seatbelts on themselves or others, and those who go helmet-less on cycles, skateboards or rollerblades:

“My kids complain if I buckle them in.”
“I don’t want to be trapped in my car in an accident.”
“If I break my neck, it’s no skin off your nose.”
“It’s none of your business what I do with my life.”

Geez, how many times has a person committing a foolish act been without insurance and been kept on life support for months, or years?

And though the question of who’s paying for the period in intensive care should not be paramount, it is a consideration.

Are we community? Is what happens to the least of us our business?

Are usury laws important to protect the uninformed and unaware and helpless? Should we support more laws to protect our citizens?

There are about 120 traffic deaths per day in the United States, far more than die in combat.

Yet we accept this loss. It is our business.