This is pretty simple stuff really. The NSA (National Security Administration) has the capability of monitoring EVERY telephone conversation (both landline and cell) in the US in real time. They use a sophisticated algorythm to check for certain key words and phrases in conversations which then tags the call and stores the data for later retrieval and review. The NSA hasn't specifically admitted it yet, but there is speculation that they have the capability to perform the same functions on international calls and on the internet. Make a call and start talking about bombs, attacks or any number of other so called "coded phrases" and you could get a visit from your local FBI agent to check out your story. Big Brother is Watching and Listening.