1. You're pretty much advocating mob rule. Also, are you seriously comparing the threat that internet hate-mongers vs. the NSA poses to the average Joe or Jane with an internet persona? I dislike corporate and government spying as much as the next person, but what immediate threat does the NSA pose to Kathy?
2. It's not hard to dream up a scenario (any immediate severe danger to one or more members of the public?) which, once the police starts believing the "witnesses", would make it irresponsible for them not to act on it. You just need enough "witnesses". From what I gather, the attitudes of some police forces, particularly in the US, could certainly do with adjusting, but that's an entirely separate problem.
3. Yes, as I'm sure you'll remember from the OP, once someone gets beaten up or worse, the authorities will take an interest. Not before that. You can't run around in real life constantly threatening people with violence, what makes it OK to do so via electronic media?