Image: Fritz Hoffman/DocumentChina

When somebody thinks the worst thing about his job is that he can't spend more time doing it, it's time to recalibrate the "job satisfaction" scale.

But that's the attitude of Duane Deal, a brigadier general in the U.S. Air Force and commander of the famous Cheyenne Mountain Operations Center. Buried under 600 meters of solid granite just outside Colorado Springs, Colo., Cheyenne is the headquarters of the North American Air Defense Command (NORAD). Deal leads North America's first line of defense against threats that range from long-range missiles and hijacked airliners to rogue asteroids and falling space debris. An aerospace engineer by training and an avid pilot, he's taken part in more than a dozen investigations of rocket and aviation accidents, including the inquiry into the Columbia space shuttle disaster two years ago.

There's not a lot of downtime in a job like that. But, in fact, that's what Deal likes best about his work. "It's the real-world mission, the responsibility that lands on our backs, the knowledge that there can be consequences of everything we do," he says.

It's also a heavy burden. "Arguably the worst part of the job is that we cannot rest in what we do," he says. "Today's realities have dictated constant vigilance, and we'll give nothing less."