Bob Wenzel over at EPJ provoked me to think about drone law a bit with this posting today: http://www.economicpolicyjournal.com/2013/01/will-personal-drones-require-further.html
Here are my edited comments on his post, as a sort of note to myself to expand on the topic a bit when I get the chance.
Airspace and oceans are areas where Lockean-Rothbardian homesteading theory, as useful as it is, does not provide very satisfactory answers to the balance of rights that should be afforded to carriages in transit over or under private property as opposed to the land holders below or above the carriage. Libertarians of the bleeding heart variety have some useful things to say about spaces that are not owned by anyone in particular, but it would require some research on my part to outline some of the prominent points of left-libertarian public space theory and relate them to the problem at hand.
Regarding flying drones, it seems to me that these should be permitted and legally protected (as property) from attack so long as not creating a nuisance, or posing an unreasonable risk of harm to any property owners below. Spying on private property may be, at least under some circumstances, a nuisance that deprives the owner of the enjoyment of privacy that owning an expanse of rock or soil might reasonably expected to provide, although the nuances of that need some hashing out. No distinction should be made between private or government drones.
Because the real estate property owner cannot determine, using present technology, whether or not a drone is spying on property below, real property owners should be permitted to bring down or otherwise disable any overflying drones owned by others, so long as they do not use an unreasonable amount of force in doing so. Such drones should be protected (i.e., subject to no more than the minimal necessary trespass on chattel required to protect the land holder's rights) and returned to the rightful owners if possible to do so, presuming that the drones are not evidence of a violent crime. What is "reasonable force" should depend on the circumstances and may change with time as drone-protection technology improves. The burden of risk for overflying another person's land should belong to the drone operator, not the land holder, based on the principle that the drone operator is the one who decides to overfly the property of another and the land holder has no say in the matter. One who intentionally and unilaterally initiates an unforced action should bear all the risks of doing so.