The gril is worrying about The Bomb.

It is, a friend assures me, a passing thing. It is, he says, just a symbol of childhood feelings of impotence in a wider and scary world.

But I think it is a symbol of her fear of the bomb.

I saw her staring into space when the idea goose-bumped across her body. She shivered and said simply, "I was worrying about the bomb."

I wanted to say the right thing to her. It is a parental flaw, wanting to say the right thing. We always want to say the right thing and end up telling them to brush their hair. So, about the bomb, I said: "It is worth worrying about." That was dumb . . . unsatisfactory.

She asked for a second opinion. It's what resourceful children do when the first answer is dumb or the source is as historically unreliable as a parent. She looked across the table and questioned a friend of ours: "Do you think I will die from old age, disease or the bomb?"

My friend was taken aback, but he is congenitally reassuring. At least, he has been reassuring me since I was 18 and worried about making a fool of myself in "Damn Yankees." He said then that I would be great. My friend is often more reassuring than accurate.

So, of course, he told the girl that there wouldn't be a nuclear war because it would be disastrous for everyone. People were too sane to drop the bomb.

The girl, however, has had a good deal of experience with the use of ultimate weapons on school playgrounds. She is not convinced that the reasonable human mind is a deterrent to violence.

So it was my turn again. This time the best I could do was wryly point out one of the values of living in Boston, one that goes unadvertised by realtors. In the event of a nuclear war, anyone this close to MIT will never know what hit her.

Double dumb.

What I wanted to be, of course, was both honest and reassuring, both accurate and comforting. But it is sometimes impossible to be both. Ground Zero is not a great comfort, especially if you are 11 years old.

This isn't the first time I have flunked my own self-administered, self-corrected, take-home parental test. Maybe I'm a tough grader, maybe we all are, or maybe the world has raised the standards over our heads.

It's not just about the bomb. It's hard to be simultaneolsly realistic and comforting about almost anything that makes life stable, or the future certain.

When we were young, most of us were fed three square meals of certainties. I don't know if our parents believed them all or if they just thought that security, like milk, was good for the children. But it was a pretty constant and even nourishing diet.

We didn't hear much about bad times, bad marriages, bad wars. The survivors of the Depression didn't talk much about it; the survivors of World War II were proud; divorce was a secret scandal.

Most of us grew up expecting a stable world. I don't think we were betrayed; at worst, most of our parents believed they could build us that world. They thought we needed to be assured instead of prepared. Instead, we were surprised.

The way we live is unexpectedly, surprisingly insecure. We live in a state of flux. Women who were going to be professional wives are working; marriages that were going to last forever exist for now. We have no vaccine for environmental diseases.

And lurking in the background is the epitome of human foolishness and insecurity: The Bomb.

And these things cannot help but affect the way we live with our own children. I suspect that they too, want a stable, secure world. They want consistency; they want answers to questions and solutions for problems.

But we can't give them what we don't have. Instead, we offer ambiguity, contingency plans, history, alternatives. And we call this "preparation for the real world."

I don't know whether they are learning insecurity and fear, or learning how to cope. Or perhaps learning how to cope with insecurity and fear. But I suppose we do what parents always do: our best. We try to share what we know of the world and what we assume they will need to know.

With any luck, we will have been too pessimistic.