1) All security has weaknesses or work-arounds. That doesn't mean that all security is worthless. Forcing adversaries to take more risks and expend more effort is kind of the whole point, and that's exactly what you're talking about.

2) Are you arguing that the actual Great Firewall, a real thing we see actually working on a massive scale, does not make it much harder for foreigners to cyber-attack China?

3) See my other post on this thread—there's work toward re-designing the Internet to make evading state- or bloc-level origin control, including communicating with existing compromised nodes inside a state, remotely, way harder than it is now. I'm talking at the node-to-node routing and backbone level. It's interesting/terrifying stuff.

4) Couple 3 with some other minor and fairly obvious tweaks to how Internet access works, and even getting a foreign device with its own infinite-range radio into the target state would be reduced to step one of several to gain access to a target state's network, and that access would likely not last long if you start doing anything weird with it.

it's just a metaphor. in reality, they're just going to use the old Patriot Act mass surveillance infrastructure, which sits inside ISPs and processes every packet.