The setting is a rooftop in Brooklyn Heights.

In the foreground, a woman tends to her baby. In the background, dark smoke rises from the Manhattan skyline.

I'm drawn to this photograph each time I visit Etherton Gallery.

I'm not the only one.

Gallery director Hannah Glasston says she can't take it down. Too many people seek out the image, which is somehow comforting in its juxtaposition of the awful and the ordinary.

It was a dangerous world on Sept. 11, 2001.

Life went on.

It is a dangerous world today.

Our bodies are fragile and our lifespan limited by biology and our penchant for carelessness, from overeating to driving recklessly to simply not paying attention.

Life is short enough and yet we find ways to shorten it further through terror and war.

Economies collapse, entire nations of people die in famine and yet we persist.

We are drawn to images of that persistence.

An emaciated mother nurses her baby in a refugee camp.

A mother tends to her child on a rooftop in Brooklyn.

New York-based photographer Alex Webb and his wife, Rebecca, were on their way to document the Manhattan bedlam when they detoured to this Brooklyn rooftop for a view of what was ahead.

Webb said the scene he captured there became his "singular image" in a day and a week of many photographs.

Maybe, he wrote for Time magazine, because it suggests that life goes on in the midst of tragedy or because it raises questions about the kind of world this child will inherit.

It often seems we are doing a poor job of leaving our children a better world. Hope, sometimes, seems an extravagance.

And yet, we rise each day.

We feed our children.

Death is certain.

Life is precious.

Each breath is an act of courage.