Robot soldiers will think, see and react increasingly like humans. In the beginning, they will be remote-controlled, looking and acting like lethal toy trucks. As the technology develops, they may take many shapes. And as their intelligence grows, so will their autonomy.

Robots in battle, as envisioned by their builders, may look and move like humans or hummingbirds, tractors or tanks, cockroaches or crickets. With the development of nanotechnology, they may become swarms of “smart dust.” The Pentagon intends for robots to haul munitions, gather intelligence, search buildings or blow them up.