Ukraine spent years perfecting cheap drone killers. After burning through billions of missiles in three days, the U.S. and its allies are asking for help.

The Defense Department this week began testing for the initial phase of its Drone Dominance Program, an effort to expand the use of commercial drones across the military. Dubbed “the Gauntlet,” ...

Mass-produced attack drones are overwhelming traditional air defenses. Ukraine is developing autonomous interceptor drones ...