Already outnumbered by its adversarial neighbor’s army, South Korea is experimenting with using armed robots to help guard the demilitarized zone that divides the country from North Korea. South Korea currently has 655,000 troops to defend itself against North Korea’s 1.2 million-strong force, and the disparity in military sizes may grow even wider as South Korea’s declining birth rate makes it more difficult for leaders in Seoul to maintain troop numbers in the future.