Think Your Cell Phone Calls Are Private?

I had a neighbor tell me that, a few weeks ago, she was on the phone with her mother.  She owns a cell phone.  I do not know if her mother was on a land line or cell phone.  She told me that she and her mother were talking about the violence in the Middle East and were innocently talking about bombs - namely all of the bombs that were going off over there.  Not about making them.  Nothing conspiratorial at all. 

And yet, just using the terms middle east and bombs warranted an interruption with a computer-generated voice that said their phone call was illegal under code blah blah blah.

Still think you're safe from such monitoring?