A Patriot missile costs around $3 million. A commercial quadcopter? Let's say roughly $200. But which one would win on the battlefield? General David Perkins, Commander of the US Army Training and Doctrine Command, knows the answer to this hypothetical David and Goliath match-up -- because it's already happened. During a military symposium, he touched on a strike made by a US ally, where the consumer drone "did not stand a chance" against the twenty-year old missile. With all due respect, sir, we could have told you that.