The Pentagon is exploring development of a futuristic "space bomber" that could destroy targets on the other side of the world in 30 minutes but could also intensify the growing international debate over the militarization of space.
As part of its program to modernize the military, Secretary of Defense Donald H. Rumsfeld directed the Pentagon last month to look into "sub-orbital space vehicles" that "would be valuable for conducting rapid global strikes," according to a planning document issued under his name.
The bomber, possibly manned, would blast off like a long-range missile and could drop precision bombs from heights of 60 miles or more. Traveling at 15 times the speed and 10 times the altitude of current heavy bombers, it would help the Pentagon overcome one of its most worrisome problems: How to destroy distant targets in light of the declining numbers--and increasing vulnerability--of U.S. military bases abroad.
Pentagon officials insist such a spacecraft would not mark a further move to militarize space because its targets would be on Earth and it would not make a full orbit of the planet. Its ultimate prospects before Congress are far from certain, though analysts pointed out that such a program could escape a direct vote if it is included in a secret "black budget" request.
In any event, the plane is sure to ignite protests from foreign governments and arms control advocates because it could be adapted to defend U.S. satellites or strike those of enemies, analysts say.
The administration's plans for military uses of space have already been under intense scrutiny because of officials' previous hints that they want to take a more assertive approach in this area.
In May, when Rumsfeld reorganized Pentagon space programs to give them more prominence, arms control advocates and congressional critics reacted angrily, accusing Rumsfeld of opening the way to placing arms in space. Arming space was "the single dumbest thing I've heard in this administration," Sen. Tom Daschle (D-S.D.), then minority leader and now majority leader of the Senate, said at the time.
Rumsfeld denied the accusation, but he and other senior officials have said that the United States--with far more satellites than any other country--needs to be able to defend itself and that technology.
While the Pentagon's interest in the bomber is conceptual, it could move quickly toward a procurement program by adapting an experimental reusable spacecraft that was under development by NASA for five years at Lockheed Martin's Skunk Works facility in Palmdale.
After investing about $1 billion, NASA canceled the X-33 Venture Star program in March because of technical problems and cost concerns.
But the military's top space official, Air Force Gen. Ralph E. Eberhart, commander of U.S. Space Command, has since expressed a strong interest in having the program taken over by the Air Force. Eberhart is considered a leading candidate to become Rumsfeld's choice as next chairman of the Joint Chiefs of Staff, the top military post.
The idea of a rocket-propelled space bomber has been around in various forms since the 1930s, when Austrian rocket scientist Eugen Sanger urged Adolf Hitler to build an "antipodal bomber" called the Silver Bird that could skip across the outer edge of the atmosphere to strike New York City. Hitler was cool to the plan, but the idea of a bomber that could streak in an orbital path around the globe has captivated rocket scientists and science-fiction enthusiasts ever since.
Rear Adm. Craig Quigley, a senior Pentagon spokesman, said the Pentagon wants to fully explore the concept because, in a crisis, "the military couldn't get anything [to a war zone] faster than this. . . . It could be useful in any number of scenarios."
Advocates in industry contend that a space bomber could be built to strike any target on the globe and return to its base in the United States in less than 90 minutes. By comparison, during the 1999 airstrikes on Kosovo, U.S. B-2 bombers flew from western Missouri to the Balkans in a round trip that lasted about 24 hours.
Advocates say such a bomber could strike key targets, like deeply buried command bunkers or air defense sites, in the first minutes of a war to make it safe for subsequent attack by other bombers or fighter aircraft.
With its speed and altitude, such a bomber would be out of reach of conventional air defenses.
Weapons dropped from the height of space would have such destructive power when they reached the ground that they would have no need for explosive warheads. They would be well suited to act as "bunker busters"--bombs that seek to pierce the reinforced concrete walls that are increasingly used to shield underground command centers.
But though this would be its initial mission, many observers around the globe would quickly focus on the extraterrestrial uses of such a fearsome-sounding plane, analysts said.
Some would see it as "the camel's nose under the tent," said James M. Lindsay, a Brookings Institution scholar and former National Security Council staff member.
John E. Pike, director of the GlobalSecurity.org research organization, predicted that, with its Buck Rogers overtones, the space bomber "would become the poster child for the militarization of space."
Europeans and Asians who are already nervous about America's growing lead in military hardware would see this technology as an unsettling new example and raise new questions about American "hegemonism," he predicted.
But others argue that the migration of the military into space is inevitable and that the United States, with the most to lose, must take advantage of promising technologies before others do.
Frank Gaffney, president of the Center for Security Policy, a pro-defense think tank with ties to Rumsfeld, called the spacecraft "one of the obvious transformational capabilities that I hope will be coming out of Rumsfeld's review" of the military.
He acknowledged that such a spacecraft "could be used just as easily for anti-satellite purposes as for targets on the ground."
Rumsfeld, who advocated a greater military use of space as chairman of a congressional study panel earlier this year, signaled his interest in the space bomber in a document that is a road map to the military reforms he wants to make.
Called "Guidance and Terms of Reference for the 2001 Quadrennial Defense Review," it offers guidance for the military planners who are devising changes to the armed forces and their strategy.
The paper is conceptual and largely avoids specifics on new military capabilities. In that context, the paper's direct assertion that a sub-orbital military space plane "would be valuable" is a strong statement of interest, said analyst Pike. The document makes no reference to how much such a craft might cost, but Pike speculated that it might run to a few billion dollars rather than tens of billions.
Over the years, designers have considered various approaches to military space planes, some with human pilots and some without. Most recent designs have involved reusable launch vehicles, in an effort to keep costs down.
One of the principal engineering challenges is developing propulsion systems powerful enough to carry the spacecraft not only through the atmosphere but also through the remainder of its trip.
Another challenge is developing thermal protection sufficient to stand up to the heat of atmospheric reentry, in which temperatures rise to thousands of degrees.
But the bigger issue is not one of physics but of cost, analysts say.
"It's very attractive, in principle," said Loren Thompson, chief operating officer of Lexington Institute, a Virginia think tank. "The key question is, can it be made affordable?"
Joint Strike Fighter: The Boeing-Lockheed Martin battle to win the contract is heating up. C1
(BEGIN TEXT OF INFOBOX / INFOGRAPHIC)
A Bomber That Blasts Off
Source: Federation of American Scientists
The Pentagon could move quickly on a "space bomber" if it chooses to adapt the X-33, which was under development for five years in Palmdale. It would be used to drop bombs from 60 miles up or more and could travel halfway around the world in 90 minutes