A number of anti-government activists used the Freedom of Information Act to have the FBI send them their (heavily redacted) files. It appears that if you are opposed to our government’s activities and make this known, there is a very good chance the FBI has a file on you.
Now to some degree I can understand why the FBI had an interest in Scott Crow. Since he calls himself an Anarchist, the historical association with bombs and that name would raise some eyebrows. But remember the FBI at this time had very few Arabic speaking agents. So to some degree what we have is looking for your lost keys under the street light because “that is where the light is.”
Colin Moynihan and Scott Shane, New York Times, 29 May 2011 via the Denver Post
"You have a bunch of guys and women all over the country sent out to find terrorism. Fortunately, there isn't a lot of terrorism in many communities," said Michael German, a former FBI agent now at the American Civil Liberties Union. "So they end up pursuing people who are critical of the government."
Complaints from the ACLU prompted the Justice Department's inspector general to assess the FBI's forays into domestic surveillance. The resulting report last September absolved the bureau of investigating dissenters based purely on their expression of political views.