Why is it that so many people's thoughts go to "killer robots" when they see a humanoid robot, but not when they see, for instance, a quad copter? Or an assembl

Why is it that so many people's thoughts go to "killer robots" when they see a humanoid robot, but not when they see, for instance, a quad copter? Or an assembly line robotic arm? Is it literally just Terminator? I guess more likely Terminator was made because it plays on a deeper psychological phemonenon—a fear of entities that look similar to us, but different. (Which presumably evolves from a rational fear of hostile outsiders to one's tribe. The same instinct that causes other maladaptive impulses in modern society, like jingoism and racism.)