Since September 11, 2001, that's been the justification for every new encroachment on civil liberties, and this time is scarcely different:
Essentially, officials want Congress to require all services that enable communications including encrypted e-mail transmitters like BlackBerry, social networking Web sites like Facebook and software that allows direct “peer to peer” messaging like Skype to be technically capable of complying if served with a wiretap order. The mandate would include being able to intercept and unscramble encrypted messages.
This logic would be a good basis for a science fiction story about the invention of telepathy, and the government's inevitable insistence that it needs to tap into our brains. Greenwald explains why this news is more extreme than it first appears:
The new law would not expand the Government's legal authority to eavesdrop -- that's unnecessary, since post-9/11 legislation has dramatically expanded those authorities -- but would require all communications, including ones over the Internet, to be built so as to enable the U.S. Government to intercept and monitor them at any time when the law permits. In other words, Internet services could legally exist only insofar as there would be no such thing as truly private communications; all must contain a "back door" to enable government officials to eavesdrop ...