I can tell when a helicopter is above me, and there is a much greater cost of operation making it impractical to use helicopters for constant surveillance in giant drag nets of innocents.
Having spent some time near an army base where they train drone pilots, I assure you that you can tell when a drone is above you too. They're not silent or invisible. Your comments border on delusional, like arguing that the existence of telescopic sights on rifles means that all telescopes are weapons.
You're right about that, I'm thinking of a different model. OTOH the price of an MQ-9 is a lot higher than that f a helicopter, and it's not the case that you can just throw thousands of them up in the air for a panopticon.
