If drones alone revolutionized modern warfare, fiber-optic tethered drones have taken it even further. The initial response to drones was to deploy systems capable of cutting the radio link between the device and its operator—but fiber-optic drones are immune to that. In this video, we see a Ukrainian fiber-optic drone entering and detonating inside a Russian bunker, which is surrounded by mesh and electronic warfare systems. How can these new drones be stopped? Cutting the cables is useless, as there are thousands of them scattered in all directions, and no one knows which are active—or whether they belong to the Russians or the Ukrainians.