It may look like a futuristic arcade game, but it’s a scene from an official Air Force animated video: Bad guys of indiscernible origin being shadowed, from a careful distance, by small robotic drones designed to resemble birds and insects. When one of the bad guys opens his apartment door, a tiny robo-bug, looking like a garage door opener with wings, sneaks in to spy. In another scene, a bug — the Air Force calls them “Micro Air Vehicles,” or MAVs — creeps into a sniper’s roost and delivers a deadly shot to the back of his head.