I truly hope that the technical problem of actually using that authority to halt the internet is as intractable as it seems--perhaps pulling the plugs on the root DNS servers would do it for the web and some other services, but many P2P networks would still be up and running.
I imagine they've already had plans drawn up for multiple scenarios. How many squads would they need to dispatch to how many server rooms before things went black? And don't forget, the NSA has hardware in high places.
