> To me this makes as much sense as the argument that since a plane carrying people can fly over you, it is perfectly reasonable to put a blimp with an extremely high zoom camera on that spies on your home constantly, detecting not just visible light, but also infrared. Also, since when you talk things vibrate, and since it is possible to view those vibrations though a window, I'm actually broadcasting my speech to the public and thus don't have any expectation of privacy.

I doubt anyone is making that argument; in Kyllo v. United States the Supreme Court held that infrared cameras constituted an unreasonable search. Recording vibrations would also likely fall in the same category.

Police spying on you from a blimp is fairly unlikely, since it would be fairly conspicuous, not to mention expensive. Far more likely they just stick a camera on a utility pole as in the recent United States v. Houston, what you're most likely alluding to. The Sixth Circuit did uphold that tactic, but the law is far from settled there.