Military transmissions need encryption to avoid interception. [fact]
Mastery over the airwaves is also necessary. In 2009, the press reported that Iraqi insurgents had managed to intercept the video feeds transmitted by Predator drones. To accomplish this, all they needed was a satellite antenna and software that could be purchased on the Internet for $26. Convinced of their own technological superiority, the American military had apparently not taken the elementary precaution of effectively encrypting their transmissions.
Grégoire Chamayou, A Theory of the Drone, loc. 296