Nothing is absolute in security.

The U.N. Security Council ordered Iraq in April 1991 to relinquish all capabilities to make biological, chemical and nuclear weapons as well as long-range missiles.

I learned the technology and tradecraft of electronic security in self defense, with a lot of expert help.

A national security letter cannot be used to authorize eavesdropping or to read the contents of e-mail. But it does permit investigators to trace revealing paths through the private affairs of a modern digital citizen.

A minimum precaution: keep your anti-malware protections up to date, and install security updates for all your software as soon as they arrive.

The National Security Agency has broken privacy rules or overstepped its legal authority thousands of times each year since Congress granted the agency broad new powers in 2008, according to an internal audit and other top-secret documents.