I surmise that the Government does have the capacity to hinder the ability to use the internet when it feels it would be necessary to protect thecurrent structure.  I feel it would be foolish to think otherwise considering all the debate's around this subject.  Which 8 years ago would
have lead everyone to believe that this issue was dead however there is no way the Government is going to allow the masses to have unlimited information and the ability to communicate in say the idea of a Civil War or Revolutionary Uprising due to Governmental Oppression. This article seems interesting to

The only true way to interrupt or possibly shut down the internet would be to destroy all the satellites that orbit the planet which would cause immediate havoc. (Totally off subject regarding a kill switch - just an off path observation).