Vast deposits of personal information sit in databases across the internet. Terms used in phone conversations have become the grounds for federal investigation. Reputable organizations like the Catholic Worker, Greenpeace, and the Vegan Community Project, have come under scrutiny by FBI "counterterrorism" agents....
It used to be you had to get a warrant to monitor a person or a group of people. Today, it is increasingly easy to monitor ideas. And then track them back to people. Most of us don't have access to the databases, software, or computing power of the NSA, FBI, and other government agencies. But an individual with access to the internet can still develop a fairly sophisticated profile of hundreds of thousands of U.S. citizens using free and publicly available resources. Here's an example.