I'm afraid that in a government of rampant spying, secret laws, secret courts, and secret gag letters, believing that people aren't being silenced because you don't hear about it requires your own personal leap of faith.

One of the strengths of the US Government is that they're smarter than to whisk people away in the middle of the night. That's why they're around and the KGB isn't. It remains to be seen whether that's a good thing or not.