Science fiction ... science fact

Which came first ... the one on the left - the stylised robot killer "dog" from Howard Overman's War of the Worlds - definitely something you would not want to run in to OR the stylised robot killer "dog" on the right - the Vision 60 Quadruped equipped with SPUR (Special Purpose Unmanned Rifle) which is designed to help armed forces get (safely) closer to enemy targets and can shoot a target from three-quarters of a mile away ... and its thermal camera with 30x optical zoom means it can spot living, breathing targets at night - making it also something you definitely would not want to run into.
So is it life imitating art or art imitating life?