"Hezbollah flew an unmanned surveillance plane over Israel Sunday. Israel said the plane crashed in Lebanese territory, while Hezbollah said that its drone had returned safely to base."
Where are they getting the money to put into R&D? I probably do not want to know the answer to that question.
My guess is that I will be about 11 to 13 months until one of these are used in an attack by terrorists. The plane probably will be built with technology you can buy from the internet. It probably will not do much damage, but that will only be the first one.
The problem with these small planes is that they will be hard to find and stop.