I suppose you are not think big (or internet) enough.

A single data center is easy to solve. Just unplug it.

What about a botnet with decentralized command and control that we will never be able to eradicate? One with so many nodes and able to hack with zero days so that any machine connected to the internet will be instantly attacked?

One botnet so powerful that we will try to build another internet so that we can actually use it again.

It’s like Kessler Syndrome, but the rocks are malicious network packets honed to exploit the recipients.