The US controls the internet still afaik.
If the internet is shut down, people won't be able to look at their p0rn, and many businesses will fail. You can bet the people who provide applications by a service via the Internet will sue the government.
Can the government even be granted such control? Does this fall under interstate commerce and/or foreign commerce? One could argue states could stand up and say "no" to a complete shutdown inside of their state.