Las Vegas is the unlikely incubator of the latest anti-terror technologies–breakthroughs born of twin concerns: how to protect the free-spending multitudes while avoiding a police state. The result is a wide-open fortress where hospitality is king and data is the best defense. Guy Martin reports on how security wagers being placed in sin city today may yield a jackpot in the war on terror

The Venetian hotel's Grand Canal is a nearly perfect Las Vegas landmark: big, innately theatrical, and completely insane. The two-hundred-yard-long indoor-outdoor waterway is home to a flotilla of "O Sole Mio"–spouting gondoliers. In the surrounding "streets," roving troupes of actors pound drums and sing bracing arias. The eighty-odd shops and restaurants draw hundreds of thousands of tourists, who sling money around as if this were the real Venice and it were their last day on earth.

Technically speaking, this is the second-floor shopping mall of the 4,027-room hotel. From a coffee shop just off the canal on a bustling midweek morning, The Venetian's director of security, Dave Shepherd, and I observe the fray. A former FBI undercover agent and counterterror analyst at the Lawrence Livermore National Laboratory, the country's top nuclear weapons research facility, Shepherd (who has since left for a private security firm) enjoys taking an old-fashioned gumshoe-level reading of the hotel a couple of times a day.

"I can get every bit of information that I might want from any law enforcement agency anytime," he says, "but I also need to walk out of my office and look at what's happening on the property. Who's here? How do things feel?" His practiced ice-blue eyes flicking over the crowd, Shepherd indicates an ordinary coffee-swilling tourist loitering just across from us with what could be a camera bag. "What's he up to, for instance?"

Shepherd and I didn't come here to observe this man; rather, we're taking a turn around The Venetian to help me understand some of the special security concerns endemic to a world-class resort.

Hotel security is practiced and innovative here for three reasons: the number of tourists with which the town is inundated, the volume of money they spend, and the length of time that hotels and resorts here have been fighting casino crime. In fact, Las Vegas has begun to export its security expertise. Shepherd himself consults with the Government Accountability Office and advises federal agencies on how to protect large structures. He and his team have just finished testing a miniaturized GPS device that can fit under firefighters' oxygen tanks so that, unlike the firemen on 9/11, they can be tracked in a burning building.

But in the perpetual throng flowing through The Venetian—fifty thousand visitors daily, roughly ten thousand more than the number of overnight travelers to Berlin—Shepherd's rhetorical question about our coffee-swilling tourist raises a thorny security issue: What can we know about this man, and when can we know it?

The Venetian security apparatus has information on him at this very moment, although Shepherd and I do not yet possess it. En route to this point in the hotel, he's been observed by an extensive video-surveillance system and a series of security officers. Shepherd won't reveal how many cameras he has deployed throughout the hotel, but they number in the thousands.