FBI doubles number of names on its "no-fly" list

I can understand the FBI taking precaution about the safety of the passengers, but I do find it kind of ridiculous that they will add you to the "no fly" list because you have credible information that my lead to an actual terroist attack that may occur on a plane. Okay thinking logically its obvious that the person was part of the master plan. But what about that person who meet someone and didn't know anything about them, then all the sudden they heard about an potential terrorist incident that may occur on the plane. We all know that the FBI has a lot of cases to close and by the time they get to the person who might not be a terrorist, his freedom of flying has been screwed. Don't we have security equipment that violate our civil rights before we go on to a flight? If the FBI is adding people to the "no fly" list, then its leads me to believe that our Airport Security is not safe at all.