In a high-security complex laden with computers, the United States Air Force is doing battle with silent and invisible enemies that many fear could wreak havoc on the country's security without ever firing a shot.
The foes include computer hackers or others who aim to penetrate or destroy computer systems and databases that are the technological backbone of the US military and make it the most powerful in history.
The job of figuring out how to defend the Air Force's computers belongs to Walter (Dusty) Rhoads and Andy Weaver, lieutenant colonels who oversee the 609th Information Warfare Squadron.
The high-tech unit, which is headquartered here at Shaw Air Force Base and armed with off-the-shelf computers, was the first of its kind created by the Pentagon.
The formation of the squadron underscores a growing apprehension in the American defense establishment. The concern is that military computers - as well as the systems that run vast portions of the country's communications, power, and commercial infrastructure - may be susceptible to attack by foreign powers.
There are already ample grounds for concern. Experts point out that in 1995, the Defense Department detected at least 250,000 efforts to hack into its databases. Many are believed to have been successful. The Pentagon is upgrading computer security.
Concerns over the vulnerability of the country's military and civilian computer systems grew after the 1991 Gulf war. The US-led Operation Desert Storm decimated the Iraqi military by destroying its ability to communicate, thereby showing that battles can be won and lost by warriors as skillful with Pentium processors as they are with cruise missiles.
Among the 609th's tasks are developing defensive measures that can be used across the Air Force, where databases do everything from plotting air campaigns to transmitting classified materials.
"It used to be, if you were rough enough and tough enough, you could roll over anybody. But in the information age, if you haven't got a good defense, you're in trouble," says Alan Campen, a retired Air Force officer and author of "The First Information War."
That's where Colonels Rhoads and Weaver come in. These former fighter pilots are charged with building from scratch an organization designed to ensure that the Air Force can protect its flank from electronic predators.
Since activating the squadron last August, Rhoads says he has counted 94 serious attempts by hackers trying to compromise the squadron's computers.
"You spread yourself thin and you cover a wide area" trying to keep up with new technologies, says Rhoads, a former Stealth fighter pilot.
In February, the 609th participated in a large Air Force exercise in Florida where it attempted to ward off "electronic attacks."
Using methods practiced at its base in South Carolina, the squadron successfully defended its databases.
The fears now being addressed by the military are seen as credible and dangerous at a time when few people expect a direct conventional attack against American forces.
Two years ago, a government commission described electronic sabotage as the gravest security threat this decade.
The scenarios considered ranged from a virus introduced into the nation's telephone switching network to electronic pulses that could threaten the global marketplace.
For the Air Force, such electronic threats could range from hackers stealing military plans, crashing computers or simply altering flight plans.
As members of the 609th acknowledge, they're pioneering ways to protect military data at a time when laptops and modems are proliferating. There are few rules and countless ideas and theories to test or dismiss.
"This is a large nut to crack," acknowledges Weaver, who once flew F-111 electronic warfare planes.
"A good adversary does not take you on symmetrically," he says. "That has to be the most important lesson to be taken out of Desert Storm."