In the summer of 2003, an Air Force pilot named Greg Harbin was doing desk duty at Prince Sultan Air Base in Saudi Arabia.

Day in and day out, Harbin sat in front of five computer screens, scanning photographs and video sent in by unmanned planes flying 1,200 miles away, over Iraq and Afghanistan.

His job was to take that information, along with reports from ground troops, and identify fresh targets — Taliban fighters or Iraqi insurgents.

But one thing puzzled him.

When regular units called for an attack by a Predator drone, the request went to Harbin, and if approved by a general, to "pilots" in Nevada, who fired the missile by remote control. The process often took as long as 45 minutes.

By contrast, special operations forces could call in attacks by unmanned Predator aircraft in less than a minute.

The difference, he learned, was that a handful of special ops units were equipped with a device called "the Rover," which gave them the same view as the pilots in Nevada. This greatly simplified communications.

He briefed his boss, Lt. Gen. Walter E. Buchanan, commander of the Air Force in the Middle East.

Buchanan dispatched Harbin to Texas to get a crash course in the Rover, a combination video receiver and laptop computer, and bring back several of the kits with him. Seventy-two hours after he left Texas with four Rovers, Harbin was in Fallujah, Iraq, teaching members of the 82nd Airborne how to use it.

For the next four years, Harbin would take a niche technology, spread it throughout the military — and help change how the Air Force fights wars.

Rover, or the Remote Operations Video Enhanced Receiver, was born shortly after the beginning of the Afghanistan war in 2002.

Christopher Manuel, an Army Special Forces chief warrant officer, had long wanted ground units to see, in real time, the video footage shot by Predators. After serving in Afghanistan, he traveled to Wright Patterson Air Force Base in Ohio to make his case. Engineers quickly developed a prototype of the Rover system.

Over the next year, it was used exclusively by special operation forces. Harbin's mission was to widen access to the technology. One of his stops was Mosul, Iraq, and the 101st Airborne Division, which happened to be the unit his brother, Eric, belonged to.

There, Greg realized a limitation of Rover: It could communicate only with Predators, and that day, the Predators were grounded by bad weather. F-15s were flying, and Greg wondered why the Rover could not connect with the cameras mounted on them.

So Harbin sent a message to Air Force officials. "Why ... can't I see what the pilot sees on his targeting pod?"

Harbin said later: "I was mad. I wanted my brother and his unit to have the best protection they could."

That touched off a chain of events leading to a new version of Rover that also could communicate with fighter planes, bombers and some helicopters.

Harbin, now a lieutenant colonel, shuttled around Iraq teaching people how to use the Rover.

In Fallujah, he showed the Rover to Marine Maj. Kevin Shea, a friend from the Air Force Academy. Harbin accepted an invitation to join a Marine patrol. Not long after the patrol rolled out of the camp, a rocket-propelled grenade flashed by with a whoosh, and a mortar round landed with a crack. As the Marines around him scrambled to return fire, Harbin sat mesmerized.

Through the din, Harbin heard a radio crackle and a voice report that a Predator was flying overhead. Through the dust of the battle, Harbin looked out of the window of the Humvee for a place to work his Rover kit.

He jumped from his Humvee and sprinted across the road toward another. The laptop's battery was dead and the Humvee had no power outlet. Undeterred, Harbin cut off the electrical cord and hot-wired the laptop to the Humvee's battery.

As the laptop powered up, another rocket-propelled grenade burst nearby. His ears rang from the force of the explosion. He turned back to the Rover. The kit worked, linking with the Predator overhead. The plane's camera sent an image of the surrounding area to the laptop's screen.

Harbin searched the video, and pinpointed the insurgents, about 100 yards away. He yelled for the Marine captain and pointed to the enemy mortar position on the screen.

The captain called in a strike. The Predator fired a Hellfire missile at the insurgents, killing them.

Harbin and two Marines were injured, one fatally. Harbin later would learn that shrapnel from the grenade destroyed the hearing in his left ear.

His actions earned him a Bronze Star, but they ended his days as an Air Force pilot. Harbin and his superiors say the Rover system saved his life and many of the Marines on the patrol.

When he returned to the United States, Harbin learned that Shea, his academy classmate, had been killed in Fallujah by an insurgent rocket in September 2004.

Over the next months, Harbin designed a Rover training course and lobbied the Air Force to purchase more.

In November 2005, Michael Wynne was sworn in as the secretary of the Air Force. He requested briefings on new technologies, including Rover. The secretary was sold.

"Greg, what you are about to do is ... change how we fight," Wynne recalls saying.

In early 2005, a year before Wynne came aboard, there were 183 Rover units in the field. There are now 1,500 of the 12-pound kits in use, mostly in Afghanistan and Iraq, and the service has ordered 2,200 more.

So far, the Air Force has spent about $72 million on Rover.

To fully equip active-duty military units, the National Guard and the Department of Homeland Security, the U.S. would need 16,544 Rover kits, an Air Force study found.

Now, Harbin walks the hallways of the Pentagon, carrying his Rover laptop in a backpack. He darts from office to office, using videos to sell the system to decision-makers from every service.

Among top Air Force officials, there is little doubt that without Harbin, the Rover might have remained a niche technology used only by a few.

"I am not the guy who invented it. I am not the guy who built it. I am not the only one who believes in it," Harbin said.

Sitting in a Pentagon cafeteria, his Rover at his feet, Harbin paused between meetings to consider what he had achieved.

"When you believe in something, you can't just talk about it and make PowerPoint slides. You have to go out to the battlefield and show how it works," he said.