BY GREG JAFFE

New York Times

FORT POLK, La. — The U.S. Army soldier steered the drone deep into enemy territory where it spotted about two dozen enemy vehicles hiding beneath a canopy of trees.

Col. Joshua Glonek recalled the jolt of excitement that ran through his staff at the drone's discovery, followed by hushed chatter in the small, dark tent where his team was preparing for what came next.

His 3,500-soldier brigade was in the last hours of an 11-day training center battle against a similarly sized force. Such exercises — the closest thing the Army has these days to actual combat — happen many times a year.

But this one was different.

The rapid proliferation of deadly drones in places such as Ukraine had set off a growing sense of alarm among the Army's top leaders.

Senior Army

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