Washington

WHEN it comes to cyberwar and cyberterrorism, we need to think the unthinkable, says veteran TV journalist Ted Koppel. His unthinkable is this: Someone hacks into the nation's electric power grid and causes large parts of it to crash for a prolonged period.

Anyone who has endured a blackout from a storm or mechanical breakdown knows how frustrating and infuriating it can be. You lose your lights, refrigeration, communications and sense of control. But two certitudes limit the anger and anxiety: first, outages are usually small geographically; and second, we know that power will be restored in days or weeks.