4phun found a Wired story that talks about the military options when a dictatorship decides to cut off internet access to its population.
"The American military does have a second set of options if it ever wants to force connectivity on a country against its ruler’s wishes. There’s just one wrinkle. 'It could be considered an act of war.'"
Hopefully the same options will be available for us when our government gets around to implementing our own kill switch