the internet is just an internetwork. which means that it's just a bunch of networks that are interconnected. not all of these networks, in all the countries around the world, are owned by the same people.
if a conspiracy like this ever did occur, there would still be pockets of large networks that would exist. networking theory is actually pretty interesting. when robert said that the internet is grassroots, that is mostly totlly true. that said, these pockets of networks could still be bridged easily by satelite or other means, and by people with money who wanted to leverage their networks more. some governments and organizations would pick up whatever slack was shed by the US.
the thing about networks, is that unlike highways between cities, they are very redundant. so you could knock out several nodes, even key nodes, and the network would still work.
but the real reason that the intrnet will never die is because the cost/benefit analysis would never work for a government to knock it out. governments make and save way too much money now via the internet. they will find a different way to control their citizens. money is power.
i know all you conspiracy ex-jws still really want the world to end, and you want to be a prophet still, spreading fear around in peoples minds so you can feel powerful. but it's not gonna happen.