By JACK HITT

THE NEXT GENERATION The U.S. military has plans for a diverse arsenal in space. Microsatellites could sabotage enemy satellites with high-power microwave beams. Flechettes are rods that could theoretically be dropped from space to smash into targets on earth. And laser cannons could, the Pentagon hopes, zap targets anywhere on the planet.

The Defense Department's newest satellite technology, Warfighter I, sits inside a protected clean room in Germantown, Md. To enter, you must run your shoes through a cleaning device and then don a "bunny suit," a layered hooded outfit that covers every part of your body except your eyes.

"Human skin sloughs off as many 30,000 particles a second," says the program manager, Michael Lembeck, as we step onto a tacky mat, essentially an enormous piece of flypaper. "If one speck of skin got on the Warfighter's lens," he adds with friendly hyperbole, "it would set us back 20 years."

The satellite, which is not much bigger than a college sophomore's dorm refrigerator, is undergoing final tests. Several different machines -- producing an artificial magnetic field, digitally created blinking stars, phony sunshine and computer-generated Global Positioning System signals -- are fooling the satellite into acting as if it were in real orbit. Several lights click on and motors grind. "It must think it just cleared the North Pole," Lembeck says, "and is reorienting itself toward the sun."

After a few more tests confirm the on-board systems are working, Lembeck says, "We'll get all the graybeards in the room, tell them what we've done here and they will bless us and say, 'Go fly."'

In fact, Warfighter I is an extremely powerful camera, one that will give the Pentagon revolutionary new powers of surveillance. But its importance goes beyond its technological wizardry. The launch of Warfighter -- scheduled for early September -- will mark the latest effort by the Pentagon to end a new threat to American security. According to the nation's war planners, America has had a free ride in space during the last 40 years, when the only country capable of even getting there was Russia. Now there is a satellite rush in the final frontier, with both countries and companies entering space. Commercial space launches started to outnumber military ones in 1998. Of the 1,000 active satellites currently in orbit, about an eighth belong to the U.S. military, and that percentage will diminish by the end of the decade, when experts estimate that operating satellites in space will reach 2,000. (Warfighter is being launched by a private company called Orbital Imaging, itself a sign of the times.)

America's war planners fear that we could soon lose our advantage in space. As a result, the military has commissioned numerous studies and long-range plans, all of them coming to the same conclusion. Space, the Pentagon believes, is the ultimate military "high ground" -- the tower from which to pour boiling oil. Therefore, America's goal there should be, in the felicitous phrase used in an early study, "Global Battlespace Dominance."

Perhaps that term sounded a little too Strangelove, for the Pentagon's preferred phrase has since become "Full Spectrum Dominance." Last year, the Air Force developed its Strategic Master Plan for space, which states our goal bluntly: "To maintain space superiority, we must have the ability to control the 'high ground' of space. To do so, we must be able to operate freely in space, deny the use of space to our adversaries, protect ourselves from attack in and through space and develop and deploy a N.M.D. capability."

N.M.D. stands for national missile defense, the controversial $8.3 billion missile shield that President Bush and his secretary of Defense, Donald Rumsfeld, have championed. (Last month, the Pentagon announced that it was ready to pour concrete on the first missile-defense test site, in Alaska.) And yet the political attention devoted to national missile defense, which is an updated version of President Reagan's Strategic Defensive Initiative, has obscured its larger purpose. According to the Strategic Master Plan, N.M.D. is but one part of a triad of technologies -- along with improved space surveillance and antisatellite offensive weaponry -- that, the Air Force hopes, will lead to total "space control." George Friedman, an intelligence consultant and the author of "The Future of War," calls the national missile defense plan a "Trojan horse" for the real issue: the coming weaponization of space.

The cost of expanding our space assets is only now beginning to show itself. Many of the specific systems for space have had their budgets increased in President Bush's first defense-spending proposal, which has been otherwise criticized for being stingy. A new system of space sensors went from $239 million to $420 million. (By comparison, the Air Force's new F-22 Raptor fighter plane has a price tag of $180 million.) A previously unfunded space-based radar program is budgeted at $50 million. And a line for "space control technology" -- a euphemism for antisatellite weaponry -- was expanded from $8 million to $33 million. Carefully budgeted space technologies like the Warfighter will cost only $42 million, but the more exotic ideas face a long climb up the technological curve and will cost billions.

Warfighter's camera features a new form of imaging called hyperspectral. Space is already home to multispectral cameras, which can take a picture of an ecosystem and discern conifer from deciduous trees. But hyperspectral goes much further, distinguishing the subtle "light signatures" that separate a field of oats from barley and telling you the precise species of oats. And then whether the field contains natural or genetically altered oats. And then whether the field is infested with insects or damaged by nitrogen depletion.

The eventual commercial potential of such a technology is obvious. But if you talk to enough colonels and experience what old Pentagon hands call "death by briefing," -- and I have -- you will hear mentions of hyperspectral quickly followed by the new mantra of contemporary war planners: tanks under trees. To put it briefly: as with oats, so with tanks. Warfighter I will be able to discern the unique light signatures of extremely specific things -- like tanks hiding under trees or tanks covered in camouflage or tanks painted with a paint meant to make them not look like tanks.

Consider what such space-assisted technology would have meant to a commander in, say, Kosovo two years ago. He could have swept the contested area with Warfighter I and zeroed in on every enemy tank, missile, ammo dump or plane, almost no matter how hard the Serbs tried to conceal them. Then the commander could have called in a cruise missile to blast each one. In theory, the entire conflict could have been finished off in time for lunch. It's a nice, sweet, hammock-tempting image if you're a war planner.

In preparation, space planners have already engaged in some feverish brainstorming. They envision a high-tech arsenal that will take full advantage of the military potential of space, ranging from the near-term possible to long-term notional: kinetic energy rods, microwave guns, space-based lasers, pyrotechnic electromagnetic pulses, holographic decoys, robo-bugs, suppression clouds, 360-degree helmet-mounted displays, cluster satellites, oxygen suckers, microsatellites, destructo swarmbots, to name a few.

Some civilians find these plans deeply troubling. "If you start talking about putting actual weapons in space, you can take the unhappiness that our allies, Russia and China already have with the missile shield and multiply it by 10," warns Lisbeth Gronlund, a physicist with the Union of Concerned Scientists. Such critics see the Pentagon's effort to weaponize space as profoundly dangerous for national security -- not to mention expensive and potentionally unfeasible.

"Once you start spinning this baby out," says Dan Smith, an analyst with the Center for Defense Information, "it becomes more complex, more expensive and more impossible to protect ourselves. After the next country introduces space weaponry, then what do we do? Live with a new, unpredictable threat orbiting right above us? Or commit an act of war by pre-emptively removing their weapons from space? The basis of security is that it never works for just one. You have to have security for everyone or it fails."

Not surprisingly, the Realpolitik leadership at the Pentagon disagrees. Just before taking over Defense, Rumsfeld led a space commission that was established not long after Congressional Republicans grew enraged that Clinton had line-item-vetoed funds for a space plane, antisatellite weapons and a missile-defense technology. The commission issued its report nine days before Bush was sworn in as president, and it concluded: "Every medium -- air, land and sea -- has seen conflict. Reality indicates that space will be no different." And Warfighter I, it turns out, is the beginning of a many-splendored arsenal to ensure we're ready for battle when it does.

Much of the military's research into space technology takes place at the Space Research Lab. It is divided into 10 missions scattered across the country, ranging from the Propulsion Directorate to the Munitions Directorate. On a blazing hot afternoon in June, I arrive at Kirtland Air Force Base in Albuquerque to get cleared into the Space Vehicles Directorate, which specializes in satellite technology. Many outposts of the emerging bureaucracy of space distill their enthusiasms into a shoulder patch. The First Space Operations's patch shows stars and a plane above the words "Always in Control." The 50th Space Wing's logo is an image of Pegasus above the claim "Master of Space." Some divisions have more informal slogans. The motto of the Space Warfare Center is "In Your Face From Outer Space."

I first meet with Alok Das, the head of the Space Vehicle Directorate's innovative concepts group. His latest work has been perfecting the microsatellite. Unlike traditional satellites, which can weigh tons, microsatellites are the size of a suitcase and weigh about 200 pounds. Since it costs "a bar of gold to launch a can of Coke," as Das put it, lightweight microsatellites will be much cheaper to launch than their obese precursors. The idea is to send microsatellites into space in flocks. In this cluster, they would be reprogrammable, able to switch to new tasks when the Pentagon required it. They might be set in linear formation to conduct ground reconnaissance or grouped in a circle to serve as a communications satellite. "It's like going from a mainframe computer to a network of PC's," Das says brightly. "Together, they'd form a larger virtual satellite."

Yet a flock could also be launched with separate missions. One microsatellite might refuel a larger satellite or upgrade its software. Others might scoot about with small on-board cameras to provide live video feeds from space -- a capability no nation currently has.

As I am escorted into a clean room to the see the first microsatellite under construction, one officer offhandedly confides, "It could also go right up to an enemy satellite and look at it real close -- maybe even bump it."

That's how easy it is to go from peaceful mission to offensive weapon. A suitcase-size microsatellite would just have to put a little shoulder and some thrust into an S.U.V.-size satellite to push it off its proper orbit and render it temporarily unable to communicate with the ground. Another idea is to mount a microwave gun on board so that once the microsatellite maneuvered right beside an enemy satellite, it could emit a pulse of microwaves and fry the electronics permanently. Space planners call this application a high-power microwave pill. Better yet, this microsatellite's sabotage operations would be covert, undetectable from earth. It would give a nation complete deniability: that Chinese satellite that Saddam Hussein has been using doesn't work? Must have been a solar storm.

The first microsatellite launch is planned for this fall.

Later, I talk with the lab's experts in hyperspectral imaging. How, I ask them, will the Warfighter learn the precise "light signature" of, say, a tank hiding beneath a pine-forest canopy?

"Think of them as fingerprints," says Tom Cooley, one of the lab's top researchers. "The wavelength of any kind of camouflage, regardless of composition, can be distinguished -- by the dyes, cotton, different lignants from plants. If you look at black-and-white images of camouflage next to scrub brush, they look the same. But a leaf from the scrub brush does not look at all like camouflage to hyperspectral. It would be sharply different."

Before hyperspectral can work, it will require some novel research and testing, says Col. Jack Anthony, chief of space experiments. "Take a tank under a tree," he says, explaining some coming tests. "We'll take some panels made of wood and paint them with different paints, government paint, some paint you might buy at a store. Then we'll take some images with the Warfighter I, and that will give us what's called 'truth."'

To build what Anthony calls "a library of light signatures," a lot of truth will have to be collected. All possible contingencies -- tank under trees, tank under branches, tank under government paint -- must be cataloged, one by one. "So if the bad guys are hiding tanks under trees," Anthony explains, "and you have a good idea what the bad guy's tank is made out of and you know what the local trees look like, then you can screen out the trees' wavelength and just see the tank's signature. Then you're going to know there's something bad under that tree. And we can arm our soldiers accordingly."

Cooley adds that "anything from Somalia to Bosnia to Haiti would have dramatically different backgrounds," making it necessary to bank in a library the differences among, say, Honduran swamps and Libyan deserts. "And by the way, water vapor is terribly opaque and will cause the special signature to be completely invisible." However, Cooley continues, another project will be to gather data in order to "correct for water vapor that may blur some of those special features."

To a civilian, hyperspectral surveillance can sound amazing and then -- once you hear about light-signature libraries and water-vapor snafus -- it can seem a bit iffy, about as dependable as launching a Xerox machine into the stress of low-earth orbit and then counting on it to work during a war.

That's how the Pentagon's critics see it. "There are already countermeasures for this kind of technology," Lisbeth Gronlund says. She describes a new kind of camouflage that entails bundling, say, two dozen Mylar balloons beside a nuclear warhead. After launch and the boost phase, the balloons and the warhead are scattered into space. Each has a slightly different light signature. So which target do you shoot down? "The military is very sensitive about this problem," Gronlund says.

Yet Anthony is doggedly optimistic. He believes that hyperspectral could be working successfully in the battlefield before the end of the decade. And he thinks the technology will help save lives: "It makes me feel good if I can help a soldier, sailor, airman, marine to know there is something bad hiding on the other side of that hill. We're just putting another arrow in our quiver."

Anthony's robust enthusiasm for space is shared among the research scientists. This enthusiasm is extraordinary. The Nasdaq bubble that burst around election time last year has not affected the military. Space-wise, war planners are prebubble techno-enthusiasts. (And their visions of space warfare are as cinematic as a summer blockbuster. Just look at the language: "Full Spectrum Dominance," "destructo swarmbots," "robo-bugs." It's hard to imagine the Pentagon's idea of space without Hollywood's.)

Inside the military, all technological setbacks -- like the fact that two out of the four major missile-defense simulations conducted so far have failed -- are set aside as part of the natural arc of any technological testing. Failure is just proof that there needs to be more research. But the real reason the military is so excited by space is that so much that is already up there, both civilian and military, works splendidly. Nearly all the emblems of our technologically quotidian life -- the A.T.M., credit-card transactions, cell phones, the Internet -- rely upon satellites.

When space technology has catastrophically failed, the public's reaction has not been greater skepticism but mere annoyance. In May 1998, the Galaxy IV satellite malfunctioned, causing 45 million pagers to shut down and credit-card transactions to cease. The public did not decide to return to making house calls, paying cash and reading by candlelight: it simply expected it to be fixed because it has so internalized the presumption that such technology works, and works wonders. And so has the military.

If the A.T.M. is the shorthand symbol of how easy modern space-based technology has made our lives, then the precision-guided munition is that symbol for the average grunt. The invention of a missile that can be aimed after it has been fired has fundamentally changed modern warfare. It is why arguments about the possible failure of new technologies bounce off space researchers as if off a force field.

Back in World War II, it took, on average, 5,000 bombs to take out one target like a bridge. By the time of the Vietnam War, the ratio had dropped to 500. But in all those wars, bombs were dumb, meaning once you let go of them, they fell in the general direction in which they were pitched.

Then came the gulf war. During this conflict, the U.S. military used space to conduct nearly all of its secret communications, reconnaissance missions and bombing raids. And space-based technology guided new "smart bombs" with such accuracy that the hit ratio plummeted to 1 in 10. "The 500-year history of ballistic warfare has come to an end," George Friedman says. "The gulf war was the first space war."

Although not of the same scale, one notable fact of the Kosovo conflict of 1999 is that no Americans died in combat. Military planners credit that result in part to munitions directed by the Global Positioning System, a constellation of 24 satellites orbiting the earth that is capable of precisely geo-locating any object equipped with the proper receiver. Couple such technological progress with the ultimate lesson of Vietnam -- no body bags on TV -- and you begin to understand the military's profound enthusiasm about space and why there has been so much blue-sky planning to maintain "Full Spectrum Dominance."

Inside the lab of the directed energy directorate, where research on everything from microwave beams to lasers begins, the machines thrum to a start. A long pipe of fuzzy purple light in a large tube seems to vibrate like a plucked string. In an adjacent chamber that has had most of the air removed to mimic the high altitude of a missile trajectory, a piece of carbonized steel like that which might clad a rocket fuel tank is set in a grip. It begins to spin rapidly to simulate a missile in its ascent. Visual access to the vacuum room is supplied by a closed-circuit television. Technicians call out from one system to another that they are ready. The machines screech into action. On the TV screen, the piece of spinning metal is suddenly blasted with bursts of columnated light that scorch it, back-splashing in a dramatic laser fan.

"We're testing the laser's effect on what would be the body of a rocket spinning in flight," says Capt. Eric Moomey, the chief of this facility. (His insignia reads "Peace Through Light.") In effect, what I am seeing is a small part of what might one day become the national missile-defense shield.

At one point, Moomey clamps a four-inch-square piece of thick plexiglass in a C-clamp and orders the crew to fire up the laser. We all put on safety goggles as the laser shouts for a portion of a second. Burned neatly in the center is an indentation, just big enough, the captain tells me as he hands me the square, to hold a coffee cup. It is holding mine right now. I suspect that my souvenir coaster is not the first of its kind.

Such laser parlor tricks suggest just how far we've come since President Reagan first suggested this idea. Back then, the technology was far off and impossible. The Strategic Defense Initiative amounted to a bluff against the Soviets, and in the end it collapsed amid political ridicule. Back in the early 80's, the idea of shooting down a missile with another missile was widely scoffed at as trying to "shoot a bullet with a bullet." The Star Wars program specifically designed to do this was called Brilliant Pebbles. Besides being technologically complex, it frightened many people with its inherent idea: ringing the planet with thousands of space-borne projectiles, each of which could drop down into the atmosphere to collide with an enemy's missile.

Brilliant Pebbles is now being revived by President Bush, but given the instantaneous speed of lasers, it may soon be joined by a companion technology. With the ability to lock onto the trajectory of a missile, Moomey explains, you might be able to aim an air-based laser at an enemy missile's fuel tank and rapidly heat up the cladding so that "the liquid propulsion vents out and it rips open like a tin can." Moomey says that this kind of laser defense weapon, budgeted at $11 billion, should be operational sometime around 2010.

I next speak with Doug Beason, another expert on laser weaponry. Colonel Beason is a thin, amiable man and a widely read scientist. His magazine rack has well-thumbed editions of Sky and Telescope, Science and Wired. He is the author (sometimes co-author) of 10 novels, including "Virtual Destruction," "Assemblers of Infinity" and "Assault on Alpha Base." A few of his works have just been issued in paperback. When I casually use the word "sci-fi" in a sentence, Beason stops me politely to say that "techno-thriller" is the genre in which he labors. Sci-fi is a "50's expression," he says, trying to be cordial, even though it's clear that I've committed a faux pas on the order of asking Jane Campion about her next chick flick. There are bright lines in Beason's world -- between techno-thriller and science fiction, but also between research that looks great on paper and technology he can help put in the hands of an American space warrior.

"The time between invention and mass use of the fluorescent lamp was 79 years," he says. "For the jet engine, 14 years; for the wireless, 8 years." This lag time is shrinking rapidly, he says. "We have the tools to exploit the technology, and that's why I'm so excited. Lasers, for example, are no longer used just for CD's and light pointers."

As a result, the Pentagon has its hopes set on a space-based laser. President Bush doubled the research budget this year to $165 million. The estimated cost for a working space laser test is about $5 billion. Actual testing in space is expected to take place as early as 2008.

"This is the technology that can provide the next revolution in military affairs," Beason says, "the Buck Rogers kind of thing."

He adds that lasers have many warfare applications besides outright weaponry. "We've also been working on a flexible-membrane mirror," Beason says, one that would be deployed in space. Then, from earth, a commander could fire a certain frequency of laser, bounce it off the mirror and "onto the battlefield to light up the night only to people with certain types of goggles."

Whenever I express any sense that these technologies sound a bit too, um, sci-fi, Beason responds the same way all his colleagues do. "These are all concepts," he explains, "and like any weaponry in a mature technological arsenal, it all depends on how much money you want to spend." Men like Beason are supremely confident in the technology; it's the political will to have space-based weapons that's the problem.

The peculiar thing about space warfare is that many of the innovations that sound the most far-fetched -- like illuminating a battlefield at night with light that only one side can see or the deployment of high-power microwave pills -- are actually much closer to existence, technologically, than some items that might seem more logically in line for development. Consider the spaceplane. It would be a tremendous tool for the military, since it could get to any point on the globe in a few hours. But building a manned craft that can quickly glide in and out of low orbits has proved incredibly daunting. Earlier this year, the X-33, NASA's big experiment in flying into space, ended in failure. The image that most people have of "Star Wars"-style combat -- manned spaceplanes engaging in dogfights near the moon -- is very far off. But the use of space for weaponry directed back at earth or guided from space is pretty much at hand.

"I'm particularly excited about high-power microwaves," Beason tells me. Lacking the thousand-mile reach of lasers, H.P.M.'s, as they are called, can be projected only about a half-mile. But were an unmanned plane guided from space able to transport a high-powered microwave device close to a battlefield, the possibilities could push the Pentagon's bomb-to-target ratio even closer to perfection. To an invading army of modern soldiers, a massive hit by high-powered microwave could ground their high-tech weapons, leaving them to wage modern warfare with their fists.

The time lag between the current R.&D. on microwaves and its application in the battlefield may be a while. Beason himself estimates 15 years, although one use is on the verge of showing up in battlefields soon. On the ground, a microwave weapon could be used to drive back an invading squadron. "It'll feel like opening the door of an oven," Beason says. "We're testing it on humans now." He pauses and worries that he is bumping up against classified information. "If you want to know more," he adds, "you'll have to contact the Human Effectiveness Directorate."

he Pentagon's passion for space also derives from the thrill of discovering the medium's own peculiar disadvantages and advantages. True, you have to worry about new problems -- space debris traveling at 16,000 miles per hour, solar flares, the Van Allen radiation belt. But it is never overcast in space, the field of vision is planetary and the speed of light is really, really fast. For the far term, war planners have conceived scores of new and exciting weapons. Talking about them is not a conversation the military wants to have in public, given the gnarly debate over the missile shield, but it is one they have been having in private for some time.

Among the internal reports generated by the war colleges and service branches are a half-dozen that imagine how space will be integrated into the U.S. military: The Strategic Master Plan, New World Vistas, Long Range Plan, Guardians of the High Frontier, Almanac 2000, Joint Vision 2010, Spacecast 2020 and Air Force 2025. Taken together, they form an encyclopedia of our war planners' dreams.

Any military response in the future would rely heavily on technologies aloft in space or directed from there. As a result, the U.S. Air Force will little resemble the service as we now romantically conceive it. According to a study entitled Counterair: The Cutting Edge, "uninhabited aerial vehicles will be widespread in 2025." Our new fleet of pilot-free planes would be directed from space and would range from small devices permitting a squadron leader to see over a hill to much larger craft that could deliver powerful weapons to a distant battlefield with tremendous speed. For example, one notion for an unmanned space-directed vehicle -- called Strike Star -- could "loiter over an area of operations for 24 hours" to deliver "stun bombs' producing overbearing noise and light effects to disrupt and disorient groups of individuals."

Weapons like the Strike Star would exist on earth but be orchestrated from space. If we can get used to the idea of weapons actually in space, though, then a new arsenal would emerge. For example, if a laser cannon were to be inserted in space, its potential as an offensive weapon would make a cruise missile look like a firecracker. Why? Because, according to one study on directed energy, "a full-power beam can successfully attack ground or airborne targets by melting or cracking cockpit canopies, burning through control cables, exploding fuel tanks, melting or burning sensor assemblies and antenna arrays, exploding or melting munitions pods, destroying ground communications and power grids and melting or burning a large variety of strategic targets (e.g., dams, industrial and defense facilities and munitions factories) -- all in a fraction of a second."

Just as the sea and the air presented different advantages in maneuverability, so will space. Having a weapon up there means being at the top of the "gravity well"' so that the force that frustrates rocketeering is suddenly your friend. "Kinetic energy weapons" are the subject of a study included in Air Force 2025, with one application being rods, or "flechettes," designed to be tossed down to earth from space. Like the legendary penny tossed off the Empire State Building boring 10 feet into the sidewalk, flechettes could travel at supersonic speed (by aiming a laser just in front of them to create an "air spike," eliminating most of the effects of shock and heat). At such a speed, they could pierce the earth's surface to a depth of one-half mile and obliterate a hidden underground bunker.

Another idea is to set into orbit a number of "giant mirrors" that would take a boy's notion of burning ants with a magnifying lens and loft it into space. "This concept constructs a 10-kilometer magnifying glass or focusing element in space to illuminate targets on the ground or in space," reads one report touting it. "This illumination can turn night to day on the ground, scorch facilities or overheat satellite components." There is a database of such ideas at the Air War College in Alabama. This "solar energy weapon" is colloquially known as "concept No. 900163."

What precisely some of these concepts do is not known, but their names can be tantalizingly glimpsed in footnotes throughout the reports that reference the space database. For example: No. 901178, "space debris repulsion field"; No. 900168, "meteors as a weapon"; No. 900231, "gnat robot threat detectors"; No. 900288, "swarms of micromachines"; No. 900390, "holographic battlefield deception"; No. 900522, "space-based AI-driven intelligence master mind."

In these internal documents, real-world constraints like political will are postponed and the enormous issue of cost is finessed. The one roadblock that is seriously addressed is the bureaucratic resistance from pilots upset at the very concept of unmanned warcraft. In such moments, the tone of the language is melancholic -- the problem referred to sorrowfully as "pro-pilot bias" -- and suggests that listening to such woes is akin to hearing out the complaints of old sergeants a century ago harrumphing about all that crazy talk of a horseless cavalry.

n a clear blue Colorado afternoon, a bus with high-security officers, civilian engineers and computer techies rumbles into the entrance tunnel to Cheyenne Mountain, the underground cold-war city built on giant springs to withstand a Soviet ICBM attack. I have come here to try to see the emerging space bureaucracy, the elements that may one day make up a new branch of the military, the United States Space Force. At the first checkpoint, we set out on foot. A cool persistent wind practically pushes us through the 30-ton blast doors. For most of the last 40 years, Cheyenne was famous for being the home of Norad, the North American Aerospace Defense Command -- the U.S.-Canadian early-warning system that scanned the globe looking for the telltale launch plume of an intercontinental ballistic missile. In fact, it is a Canadian officer from Norad who escorts me into the command room and to the chair where a commanding general would make the decision to launch a nuclear weapon.

"Don't mash the distress button under the desk there," the Canadian warns me, "or armed guards will storm the room." Before me are a wall of television screens reporting global data. (On account of my presence, several are draped with blankets marked Top Secret.) And right away, the shift toward space is obvious. The main screen reads "Combined Command Center for NORAD/USSPACECOM."

The U.S. Space Command is the proto-bureaucracy of our emerging space force. Its current commander, a four-star general named Ralph E. Eberhardt, was given more prominence last May when Rumsfeld reorganized the space command structure. Eberhardt is being touted as the possible next chairman of the Joint Chiefs. Should he be appointed, it will be the most powerful signal yet that President Bush's campaign promise to "leapfrog" to the next generation of weaponry will mean the militarization of space.

The clearest evidence is across town from Cheyenne at Schriever Air Force Base. The Space Warfare Center was established there in 1993. It has three branches, the Space Battle Lab (patch: "Above All Others"); the Space Warfare School (patch: image of missile shooting off lightning bolts); and, as of last October, the 527th Space Aggressor Squadron (patch: image of cartoon bird standing on a cloud tossing a missile to earth). A good deal of the theory about how space can assist our troops during wartime on earth -- today -- is being developed here. It is the Space Battle Lab that will soon be figuring out how to take a reading from the hyperspectral camera aboard Warfighter I and make that information meaningful to a pilot flying an Air Force bomber.

We are trying to bring the utility of space directly to the fighter," says the battle lab commander, Col. Ron Oholendt, "by either increasing lethality or mission effectiveness." Another project under way is to make better use of space for "bomb-impact assessment."

"As a cruise missile is heading for its target," Oholendt says, "it would transmit a data burst into space just before impact. It might tell us, 'I'm armed; here's where I am; the scene I see matches the target I was given.' So we'd have a confidence it was successful. Or it might say, 'I'm here; I don't see anything familiar so I'm going to blow up some dirt.' After we downloaded the information from the satellite, we'd be fairly confident that site would have to be retargeted."

Rumsfeld has said that the military must prepare itself to avoid a "space Pearl Harbor." This is where such preparations are being made. The commander of the space aggressor squadron, Col. Conrad Widman, spends his days envisioning how an enemy might exploit space -- in order to train our forces how to react.

"The one thing you don't want to do is go to war and encounter the enemy's capability for the first time," Widman says. In one simulation exercise, he and the 527th posed as an Iranian terrorist cell set against some real U.S. troops stationed in South Asia. During the exercise, Widman hired a French satellite to take a picture, which can be paid for with a credit card.

"The guys on the Iranian team were able to count airplanes and see entry control points," Widman explains. "They could even see the tent-city area and figure out how many people they had deployed. They could also tell there was some kind of air-defense batteries. They knew that Patriot missiles often played that role, so they went to the Raytheon home page and learned that Patriot batteries are normally laid out in a format with the radar in the center." By the time the 527th had finished the simulation, they had learned the surrounding landscape, the best approach path and the entry points into the concertina-wire-protected camp.

"Is this how the terrorists in Yemen figured where the U.S.S. Cole was?" Widman says chillingly. Widman's work repeatedly reveals that technologies once carefully held as national-security secrets are now commonplace because of satellite proliferation and the Internet. "More and more," Widman's colleague Col. James Rogers says, "the problem is not another superpower, but a guy with a credit card."

As a sign of space's growing importance to the military, the first large-scale war game devoted to space issues was held for five days in January. The hypothetical conflict was set in the year 2017 and involved fighting a space battle with a "near-peer competitor" country named Red that resembled China. During the simulation exercise, which involved 250 people, the two main weapons used to duke it out were laser cannons and microsatellites. Even though select journalists were invited to "watch," the Pentagon did not provide many details of the fighting, except to say that the conflict hinged on attempts to blind each other's satellites as a first step toward waging war. The message of the demonstration, however, was clear: whoever doesn't control space in the next conflict will lose.

he future of space depends a great deal on how we describe it, a struggle that is largely metaphorical. Is space merely an extension of the air and therefore the province of the Air Force? Or is it an entirely separate medium for power, like the land or sea, in need of a new doctrine? The first comparison more easily allows a militarization of space as just more of what we already have, while the second challenges us to debate space as the frontier it still is.

Rumsfeld leans toward the first comparison. His reorganization of the space command structure two months ago put Eberhardt and the Air Force in charge. The changes are even linguistic; the Air Force has revived the antique word "aerospace" to remarry the two domains. The Strategic Master Plan, for example, describes the current Air Force as being engaged in a "transition from a cold-war garrison force to an expeditionary aerospace force" in order to train "21st-century aerospace warriors."

At every stop, I was reminded of the incremental militarization of air after World War I. The Air Force began as a wing of the Army, flying over enemy territory and providing surveillance. Then the pilots began shooting one another down; later they started to drop bombs. Space can be seen as undergoing the same process, progressing out of its current stage as an arena of surveillance to microsatellites attacking other satellites to, finally, space-based lasers aiming down at fighter jets to blast them from the sky.

Yet at some point the future of space will emerge as a great American debate. Over and over, as I interviewed military scientists and generals assigned to space, I was reminded that the decision to move into space will, at the end of the day, be made in Washington. Already, a few politicians have foreseen this conversation and staked out positions.

"Space is our next manifest destiny," explains Senator Bob Smith, Republican of New Hampshire, "because it's a dangerous world out there." Smith says that we have to weaponize space before somebody else does or face the consequences: "I don't want to see a president in the position where he has to step up to the microphones and say that the next Iraq has threatened us with a full-scale attack tomorrow, and we've either got to surrender or nuke them."

On the other side is Representative Dennis Kucinich, Democrat of Ohio. This fall, he intends to introduce a bill to ban completely the weaponization of space. "It's bad enough that we've turned space into a junkyard, but they want to turn space into a place of death," he says. "Think about the metaphysics. For all of human history, space was a place of wonder, of dreams, of aspirations -- an almost visual portrayal of Browning's poem: 'Ah, but a man's reach should exceed his grasp,/Or what's a heaven for?"'

Ugh. Maybe this is how the debate must begin -- duck-and-cover fear-mongering versus mawkish piety. Yet both positions are really built around the same fear: weaponizing space is terrifying. Smith resolves his fear by weaponizing first; Kucinich by appealing to a pristine notion of space that hasn't existed for 40 years. But this fear is real precisely because space weapons, unlike those at sea or on land, would orbit invisibly above us all. That fear would be irresolvable, like the nuclear nightmares of the last century, with their bomb shelters, gas masks and decades of mass-destruction anxiety. It is bad enough that space-surveillance technology has conspiracy theorists convinced the government can see them stepping out of the shower. Can you imagine the global neuroses if deadly lasers could be fired from space?

There is, however, a middle ground between hang-nukes-from-every-star and leave-space-the-inky-domain-of-magi, one that is occupied by some civilian theorists and military war planners.

"If we aggressively move weaponry into space," warns Michael Krepon of the Stimson Center, a Washington think tank, "then we will start an arms race." By inspiring nations to compete directly and immediately with our space-based assets, we will almost certainly guarantee the loss of the very advantages we seek to protect. Krepon supports a doctrine called "space sanctuary," a woolly phrase that sounds more feel-good than it is. His position is really that of a space pragmatist.

Pragmatists like Krepon want the military to continue research into space technologies; it would be foolish not to do so. But instead of testing or deploying a space-based arsenal, pragmatists would hold up a threat: if any rival country goes into space to test armaments, then America will go up with its own devices immediately. In the meantime, pragmatists believe, the United States should be promoting efforts to create rules of the road for space. As a model, Krepon suggests the bilateral agreements that currently regulate behavior among blue-water ships on the oceans. They are informally negotiated navy to navy, rather than through the more potentially hostile venues of governments and treaty arrangements.

Space pragmatists also believe there is great danger in abandoning the treaties that so far have guided behavior in space: the 1967 Outer Space Treaty, which forbids putting weapons of mass destruction in space, and the 1972 Antiballistic Missile Treaty, which created the surveillance system to prevent nuclear conflict (and forbids most antimissile testing). President Bush has roundly condemned the ABM treaty as a "relic" and has said that he will test antimissile technology no matter what -- prompting precisely the kind of reaction Krepon fears. Even our allies have expressed "concern."

"If the ABM treaty is trashed, its protections of satellites also go by the boards," Krepon cautions. "The ABM treaty contains the most explicit protections of satellites on the books. They pertain only to those satellites that monitor treaty provisions, but when you kill the treaty, you also remove the protections." Indeed, if the U.S. abandons the treaty, a rogue nation might well respond by tossing into orbit what experts call a "keg of nails" -- that is, putting thousands of metal shards into a 16,000-mile-per-hour counterorbit against our low-orbit satellites.

Kaboom.

The Pentagon's certainty that "Full Spectrum Dominance" is the only answer is curious because its own actions undercut the theory. Throughout all the conversations I had, I was perplexed by one glaring paradox. The linchpin of our precision-guided munitions is the Global Positioning System. After making the system public in the 90's, we opened it up further two years ago so that anyone on the earth can use its efficacy down to one meter of accuracy. This is an amazing gift to the world. Why did we make it? I kept asking the officers this question and heard an answer that didn't quite satisfy: "American businessmen could make some money off it."

But there is one other theory that is not stated so publicly: if we permitted everyone to use it, then no one would feel driven to build a competing system. Rather, everyone would become dependent on it. And, in fact, everyone has. The world has incorporated our G.P.S. into its daily life as rapidly as Americans took up the A.T.M. banking network, and the rules of the G.P.S. road are getting written. The entire military forces of Australia now rely upon our G.P.S., and the new generation of cell phones will automatically locate a 911 caller.

By sharing G.P.S., no one feels so threatened to compete with it. And its use is so ubiquitous internationally that any country that damaged it would provoke a global fury. There is a sense of transparency on our part by giving away access to the G.P.S., even a feeling of generosity. Naturally, there are encryption devices on our satellites. In a crisis, we could block a bellicose nation's access to G.P.S. What was done with G.P.S. is a kind of space pragmatism.

A similar protocol could be done for introducing direct video access to space. Once it is developed, the U.S. military could make technology that allows us to see and confirm exactly what is happening up in space publicly available. This would, once again, be viewed as American generosity. It would ease competitive tensions since there would be mutually assured awareness in space. A nation with a defunct satellite would be able to confirm that it was not sabotage but the usual wear and tear of, say, subatomic bombardment (another new space hazard) that caused a breakdown. The benefit for us would be that when the crunch time of a crisis came, the visual infrastructure to see precisely what's going on in space, like G.P.S., could be made unavailable to a hostile force.

The strength of the pragmatic position is that it seeks neither to march into space while locking and loading nor does it naively strive for a purity that no longer exists. Space pragmatism doesn't pretend to keep space unsullied, because it can't. Without a doubt, more and more satellites will go up. More businesses will operate there, new uses will be discovered and quarrels will occur. And gradually, a military presence that is already there will get expanded. But the pragmatist intent is to hold the line at surveillance.

Can we? Can we hold the line without necessarily filling space with weaponry? The pragmatist position holds out the hope that by writing rules now -- and by sharing technology -- the United States could make it much harder for anyone to ever breach that line. On the other hand, if we plan, test and deploy aggressively as the lone superpower, we make certain that after a brief respite from the cold war's nuclear competition, we will once again embark on a fresh and costly arms race. And with it, assume the dark burden of policing a rapid evolution in battlespace.

Jack Hitt is a contributing writer for the magazine. 
NYTimes Aug 5, Magazine