Very hard to shoot these things down because it's almost impossible to detect them and air-to-air missiles aren't designed to operate at 70,000 feet.  

Flight speed is anywhere from "loiter" to over Mach 5.  

A reliable anti-drone weapon system hasn't been specified, designed, tested, and deployed.  

Given the low cost of drones, to purchase and to operate, versus other "force projection" weapon systems I doubt they will become obsolete in our lifetime.


She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre