The government can shut down everything in a heartbeat including Cell Phones, Internet, TV, transportation and scramble all radio communications and do it at will! Never think they don’t have a plan to do so either... We pay lots of people to strategize on every kind of what if scenarios could happen. Trust me there is a plan in place for what if's.
Trust me on this one!
As I've said before, I fully expect the military to have plans for repelling martian invasions. Real plans. Plural.