Internet is an supra-state entity.
It’s an extraordinary phenomenon in our history, like the domestication of electricity.
After all, who ever said that countries, especially in the decadence of today’s fashion of so called “nations” – actually overgrowth weak bureaucracy/money hunting systems, are something ultimate, finished? Just because it was suitable at some point in our evolution doesn’t mean it will be suitable after that. Mankind is waiting for a completely different organization structure, a one to be closer to the perfection of balance and symmetry.
Let’s say they can even block it, turn it off, but in this way they block and turn off themselves, their economy and growth. The pressure of the technological evolution is quite a serious event, in fact.