The "no one ever imagined" line is put forward by DC insiders to cover for the fact that they never planned for a well known attack vector. Reporters spend a lifetime building connections to senior civil servants and have no problem running with lines like that if it will help their contacts keep their jobs.
http://en.wikipedia.org/wiki/The_Lone_Gunmen_(TV_series)
The "no one ever imagined" line is put forward by DC insiders to cover for the fact that they never planned for a well known attack vector. Reporters spend a lifetime building connections to senior civil servants and have no problem running with lines like that if it will help their contacts keep their jobs.