[mindcrime]

But for that to cause real trouble, you'd need coordinated action that would require something like a state level actor.

Or thousands of individuals using relatively inexpensive HackRF One SDR's, or home-brew radio transmitters which can be built even more cheaply. Of course all those people would need a way to communicate with each other over large distances... perhaps some kind of packet switching network running over a series of tubes (or avian carriers). Hmmm.