LAS VEGAS -- This city, famous for being America's playground, has also become its security lab. Like nowhere else in the United States, Las Vegas has embraced the twin trends of data mining and high-tech surveillance, with arguably more cameras per square foot than any airport or sports arena in the country. Even the city's cabs and monorail have cameras. As the US government ramps up its efforts to forestall terrorist attacks, some privacy advocates view the city as a harbinger of things to come.
