Wladimir van Wilgenburg stands in a residential neighborhood in Erbil, in the Kurdistan region of Iraq, and points out incoming drones high in the sky. "The U.S. defense systems, as you can see, are taking down the drones," he says in a video recorded ...

Instead of the heavy systems used by the U.S. military since World War II—missiles and ships that are expensive to design, build, and operate—this war is powered by swarms of mass-produced and oft-autonomous drones that can do the job cheaper and faster.

Inexpensive fiber-optic drones are challenging Israel's high-tech defenses, shifting the military balance in the Middle East.

Israel’s government says Hezbollah’s use of small commercial drones is a tactical concern, but not a game-changer. Nonetheless, Israel says it will escalate its attacks on Lebanese targets to try to address the growing threat.

Deep in the Russian republic of Tatarstan, far from the front line and away from scrutiny, a factory complex has quietly become the engine of the most intensive drone war in history.