The only way I can see of destroying the Internet would be to destroy each and every server connected to it. Since the Internet is really just a web of connected servers, it would be nothing without them. The problem with that is that servers are everywhere! How would you find and destroy every one? The first servers you'd probally want to destroy would be DNS servers. These hold all the domains for websites. If they were to be cut out, the sites would still exest but there would be no way to access then via typing in a URL!