One of the enduring aspects of American culture that other people around the globe view as remarkable is our willingness to welcome and embrace change.

One time in the 1980s I was interviewing people in northern Mexico when that land was seeing enormous technological and social upheaval. In conversation, I kept referring to their transformation as a "revolution." Finally, one person brought me up short. Can you please find another word to use other than "revolution," he requested politely but firmly. We northern Mexicans remember what revolution is like. It is bloody, and despicable and awful. Only you Americans find the idea of revolution exciting.

I thought of that moment Saturday as, with everyone else, I watched the film over and over again of Columbia breaking up. It was awful, and unspeakably sad. We worried about what auguries it might hold. My daughter's first question: Was it the Iraqis, Daddy?

Yet, somehow, this disaster wasn't as gut-wrenching as Challenger. For all the anguish of this shock, it felt almost antique, as if we knew how to reach back to process these moments. As all the broadcasters noted, it was as if we had come to take spaceflight for granted -- even, alas, the disasters. After all, as the stuff of dreams and nightmares, rockets have been around now for almost four generations.

This may be noteworthy because of the new shocks we are about to live through. As it happens, our emerging technologies are leading us into a period of unprecedented cultural upheaval. Something genuinely revolutionary on the face of the Earth is being born. We are riding a curve of exponential change that is altering no less than what it means to be human.

These new changes are not about chemical propulsion taking us into orbit, as important as that technology has been to our ways of communicating, of dealing with the weather, of visualizing ourselves as part of a whole Earth and a beautiful universe, and of waging war.

Now, for the first time in human history, our technologies are not so much aimed outward -- to conquer the stars for example, as in the case of space travel. Instead, we are now aiming inward. We are entering an era in which we are beginning to change and enhance our thinking, our memory, our personalities, and perhaps our souls. We can see the day coming in the next decade or two when we will be manipulating some real fundamentals about human nature. Like whether we need to sleep. Whether we need to age. Whether we will be able to instantly understand languages that we have never before heard, thanks to machines wired to our very brains. These changes stretch the bounds of what seems possible -- gear exists, for example, to allow experimental monkeys to control distant machines with their thoughts.

Sound like science fiction? Not long ago, so did space stations such as the one that shuttles like the Columbia routinely supply.

What's intriguing about all this is the equanimity with which we Americans are approaching this future. Nearly half our grain had become genetically altered before there was much of a kickback. For we assume our futures will be successful or at least fixable. And correctly so, some argue. After all, the grain alterations were meant to improve the environment by, say, lessening the need for chemical pesticides. We are practical people, we Americans. When weighing cost vs. benefit, we don't respond well to theory. We ask to see the harm. Could such a day of reckoning come? Of course. But until then, we seem to face change with composure.

Which is not to say we are incapable of taking moral control of our technologies. One of the least likely futures of the last half century, when you think about it, is the one we are living in today: No nuclear weapon has been exploded in anger in 58 years. Of course, this could go badly awry tomorrow. But that's a risk we've clearly understood for a long time, so we've erected elaborate mechanisms to manage it. So far, miraculously enough, they've worked.

Along these lines, it will be interesting to see how we handle human clones. Few doubt that the technology to create such creatures will exist in 20 years -- if not next week. The question is how our culture and values will respond. Will we view such clones as commonplace -- as unremarkable a babymaking technology as in vitro fertilization and amniocentesis is today? Or will we view them as anathema, a horrible mistake that should never be repeated? My hunch is that once again, we will respond not to theory, or theology. We will see how the first ones work out, and decide at that point whether or not to recoil in horror.

Which brings us back to Columbia.

This has been an immeasurably sad weekend. We won't forget it. Columbia's crew of varied hues and nationalities and genders has doubtless already taken a permanent place in our folklore. We imagined a crew just like this one in television fiction 37 years ago. Then we matched "Star Trek" with science fact.

The question is where this tragedy takes us. Soon, certainly, the Op-Ed articles will appear again questioning the value of putting men and women into space. It's expensive, it's awkward, robots can do it cheaper, faster, better -- you've heard the whole argument. And those arguments are all correct.

Except, perhaps, that they miss the point of how we Americans handle change. As my Mexican friend noted, we Americans find revolutions to be exciting. Damn us as naive and shallow, if you will. But we really do believe in progress.

Americans are part of a wildly individualistic, determined culture that may or may not know how to resolve dilemmas, but that does attack obstacles -- compulsively and reflexively. Americans believe, endearingly and in spite of all evidence, that for every problem, there is a solution. Responding to a challenge by doing nothing is not our long suit. There is little more foreign to an American ear than evil accepted. "What will be, will be" is no more from our language than the phrase "It is God's will." Fatalism is outside our repertoire.

So yes, we will listen to the arguments for not risking the lives of brave people. And we will agree that robots in space can do marvelous things, as the astonishing pictures from the Hubble telescope have shown. And if there is blame to be assigned for the Columbia disaster, we will apply it with a vengeance.

Then, when it's over, we will probably go back to agreeing that space budgets are only tangentially about manipulating chemistry in hard radiation or growing cells in microgravity.

As has been demonstrated by the rich American tourists who have paid their way through the Russians to visit the space station, there is only one question we really have, and it's a pragmatic one that reflects who we are, how we got that way, where we're headed and what we value.

What we want to know is when do we get a crack at this future ourselves? When do we get to taste it and feel it and test ourselves against it personally?

What we really want to know is:

When do we get to go?

Yes, robots in space can do astonishing things -- witness the Hubble photographs. But is hard science the only reason we venture?Columbia's crew of varied hues and nationalities and genders, below, has doubtless already taken a permanent place in our folklore. We imagined a crew just like this one in television and movie fiction years ago. Then we matched "Star Trek," above, with science fact.