Comments by "Arthur Mosel" (@arthurmosel808) on "US shoots down third 'object' after initial Chinese spy craft" video.

Very little actual radar is in use. Most aircontrol is done by devices reading IIF. As to what the payload could be, most probably some sort of intelligence gathering equipment; however, they could be used to spread toxic materials, diseases (Japan tried that during WW2), or an EMP device. The three nasties mentioned are possibilities; disease payloads are probably the least probable since you would have to find a way to keep the organisims alive. Toxins are somewhat more possible possible, the amount needed and its dispersal is the problem there. Something like fenantyl where a small amount is highly toxic released over a dense urban area could create havoc if done under the right conditions, especially if the device was not registering on any form of radar andnot highly visible from the ground, somewhat more possible than the disease scenario. The most possible is some type of EMP device (not necessarily anuclear weapon). The havoc that such a device could cause would be horrendous on the economy and possibly cause sarge scale loss of life due the failure of devices like pace makers as well as those potentially lost to societal breakdown. I rate this as the most probable of the three scenarios. A number of countries, including the US either are working on or have worked non-nuclear EMP weapons.
1