"I may not agree with what you have to say, but I will defend to the death your right to say it."
Edit: People keep talking about how this incident is a sign of how evil and scary Bush&co are. Except, that really isn't what this is about. And Annie even says as much! [Not that she didn't say as much in her first post on the matter, but after everyone and his dog declared that's what it was about, she posted a clarifying entry.]
I'm not linking to what everybody and his brother has already linked to, though I will happily point out that anniesj is not claiming that her civil rights were violated. She's warning people to watch their phrasing, if they'd like to avoid the same thing that happened to her. And also giving a heads-up that one twit on LJ who thinks it's amusing to report someone they don't like to the federal government means there's probably more than one. The fact that people are freaking out to epidemic proportions in her comments is not her fault.
I'm with Pet that the issue here is not Big Brother, but Bitch-Ass Sister, i.e. the twit who was either stupid enough to believe that Annie's post constituted a serious threat, or as seems more likely, reported her to the government out of spite. Though I find it indicative of the political climate we're currently living in that said twit even thought "Hey, I know how I can get even! I'll report her to the Secret Service!"