"Technology changes slowly, but political intentions can change very quickly. In 2000, I wrote in my book Secrets and Lies about police surveillance technologies: "Once the technology is in place, there will always be the temptation to use it. And it is poor civic hygiene to install technologies that could someday facilitate a police state." Today we're installing technologies of ubiquitous surveillance, and the temptation to use them will be overwhelming."
http://www.theatlantic.com/politics/archive/2013/07/mission-creep-when-everything-is-terrorism/277844/