As for the power companies, I'm sure thats why they hire security professionals like yourself :).
The SEC provides regulations.
Billions don't need to be sunk by defense agencies on what is essentially a regulation issue.
A lot of these doomsday scenarios are bullshit. The world ran fine without cell phones and the internet, it'll run just as fine without it for a little while. Aside from a medical case here and there, noone is going to die and no country will dissolve as a result of being hacked on the internet or even being without power for a little while.