The principal cause of Israeli aircraft crashes are bird strikes which cause way more losses than enemy fire. Israel is located on the main north south route for birds going and coming between Africa and Europe. Similar bird routes are around the globe and pose similar hazards, not least from a crafty attacked who would use them to hide conventional anti-air swarms of mini-craft. It has been suggested that a pretty good anti-air campaign against Israel would be swarms of birds blending in and supplementing natural ebbs and flows. Swarms of mini-drones, the little ones which are unarmed, not much bigger than a model plane, could be effective against UAVs as well as full-sized aircraft. These cost a few hundred dollars, and are hard for radar to distinguish from birds. There is concern that such mechanical swarms might be used against commercial airliners, with or without camouflaging bird flocks. Some are very quiet, running on batteries not the customary noisemakers. Can a disposal drone home in on a soldier's radio signal? Sure, using the same signal technology as model planes. Call them snipers for assassination politics. It is reported that the US military is working on similar systems. Some are water-borne to go after surface ships with a radar profile no different than a wave or a leaping fish. No doubt a submarine version is in the works or already exists. Put the armed dolphins out of work. The point is well-made that these cheap attackers pose a threat to nations highly armed with heavy weaponry aimed at its own kind.