Yesterday's New York Times has a story about Google Earth, a relatively new satellite image program that allows anyone with a computer to access--free of charge--aerial photographs of locations around the globe.
According to the Times, governments here and across the planet are nervous about Google Earth, because it allows you to peruse--in sometimes startling clarity--government buildings, military installations, and other sensitive locales.
The article focuses on the federal government and foreign countries. But the homeland security concerns for state and local governments seem pretty obvious.
See, for example:
The Port of Long Beach, Calif...
and the Oklahoma State Capitol building