Boston ? There is a moment when nearly every astronaut looking out from the spaceship to the great blue earth enters the same sentiment into the public travel log. From their Olympian heights, they see no borders, no countries, no demarcation lines to separate people. They report, in the cliche of space travel, that we share one planet, benign and awesome.

Now we are living with a very different and terrible reminder of our membership on a single planet. On Dec. 26, following some geological timetable, the tectonic plates deep in the earth shifted. An immense body of water moved thousands of miles across oceans and land masses, across Indonesia, Sri Lanka, India, Thailand, and all the way to Somalia.

Scientists and journalists alike described water moving “at jet speed.” The airplane, after all, is the very model of a connecting link that brings people together across time zones, continents and cultures.

Europeans had flown to the Andaman seacoast of Thailand “at jet speed.” Americans had gone to India “at jet speed.” The same planes that shrink the world, allowing Northerners to flee the winter at jet speed to share summer, had left tourists sharing a watery grave with natives.

So the earthquake knocked the world off its axis by 2.5 centimeters and shortened the day by millionths of a second. But it was in the personal tragedy we felt our unity.

Waves swept away Muslims, Hindus, Buddhists and Christians with a ferocious indifference. The tsunami took no side even in decades-old enmities over borders and beliefs.

The stories, singular in their pain, were universal in their common human denominator. The unimaginable horror of children snatched from their parents by a wave. The dazed survivors counting their losses up to a collective 150,000. The disappearance of whole known worlds, villages, families.

So too, the search for understanding was as universal, if perhaps as futile, as the search for bodies. Some survivors talked about the tsunami as an “act of God” — as if God were the fine print on an insurance policy.

Indeed, survivors described “miracles” until that word sounded like nothing but a synonym for incomprehensible, random luck. Or perhaps miracle is the answer when you run down the list of possibilities and hit “none of the above.”

Once again, unified in the face of catastrophe, we hit the pause button on our own manmade conflicts. We were caught up short in the midst of endless squabbling over our own differences. Even in Sri Lanka where 64,000 died in decades of civil war, Tamils and Sinhalese took time out to share the loss of 34,000 in minutes.

Now it’s international aid that travels to Asia at jet speed. The world sends money to victims at Internet speed. There is a worldwide conference in Indonesia and talk of creating an early warning system in the Indian Ocean.

But I also watch us inch back to “normal.” On Page 1, the fury of nature shares space again with the folly of humanity. The victims of nature make room for the victims of man-made conflict.

There is another car bombing in Iraq. People in Washington are parsing the definition of human torture. There is a story, datelined Iran, about nuclear weapons. And in the northeastern districts of Sri Lanka there are the first disheartening reports of Tamils refusing aid and government officials burning up food.

I am no theologian. In my business we prefer to avoid questions without answers. We are shy about inquiries that lurch between the profound and the naive. We set aside the sort of wondering that sets us wandering.

But it’s impossible to watch this unfold and not wonder why people need tragedy to remind us of our humanity. And why we manufacture disaster when nature provides quite enough of its own.

Not long ago, Rwanda added more than 800,000 to the wave of its human death toll. Each year, 2 million die from malaria. Is it only from the Olympian heights of outer space or the geological depths of an undersea earthquake that we feel our connection. Is it only during an “act of God” that religious wars seem absurd and suicide bombs redundant?

Even now in the wake of the tsunami, we know more about tectonic plates buried under the ocean than we do about our own heart of darkness. Where on earth is the early warning system for manmade disasters?

— Ellen Goodman is a columnist for Washington Post Writers Group.