I just replied to another thread with this exact same thought, then looked down to see yours. And yes, it is scary... If I understand it correctly, the targeting system just consists of normal receivers hacked to offset their targeting feedback by a distance that would park the energy ball inside the victim.

In any of the applications where this is deployed broadly, that is, where we cover our cities in transmitters, then we'll have effectively given over this remote kill capability to anyone who can do trilateration.