You would think that since Y2K, somebody in government or business would have come up with a contingency plan to manually override computer control in the event that something like this took place. Networked systems are fine, but we all know that everything from lightning to EMP to Gamma Ray bursts in distant regions of space could knock the computer controls out for extended periods. It's not like we don't know how to manually control the power grid. And anything that has the potential for catastropic negative externalities if hacked should simply never be connected to a network. Neither the software nor hardware should even have the capability of being networked.

Update:

"The end result is that, as part of our modernization, we've made ourselves more vulnerable," said James Lewis, a senior fellow at the nonprofit Center for Strategic and International Studies (CSIS).