What are these machines? An article in Foreign Affairs outlines the sort of technology that is moving us toward a future populated by killer robots:
The Samsung Techwin security surveillance guard robots, which South Korea uses in the demilitarized zone it shares with North Korea, can detect targets through infrared sensors. Although they are currently operated by humans, the robots have an automatic feature that can detect body heat in the demilitarized zone and fire with an onboard machine gun without the need for human operators. The U.S. firm Northrop Grumman has developed an autonomous drone, the X-47B, which can travel on a preprogrammed flight path while being monitored by a pilot on a ship. It is expected to enter active naval service by 2019. Israel, meanwhile, is developing an armed drone known as the Harop that could select targets on its own with a special sensor, after loitering in the skies for hours.