What seems to me a more realistic concern is that you could create a beam of energy that would be lethal to an individual device. Brains are typically a lot mor

What seems to me a more realistic concern is that you could create a beam of energy that would be lethal to an individual device. Brains are typically a lot more durable to EM radiation than electronics. And more generally, it seems like relying on coordinating devices you don't physically own opens you up to all sorts of new kinds of DoS attack.