Working 10 hours a day for $20 a week in a World War II defense plant 70 years ago was 18-year-old Norma Jeane Dougherty, wife of a young United States merchant seaman assigned overseas. Her company, called Radioplane, in Burbank, Calif., founded by the British character actor Reginald Denny, made small remote-controlled pilotless aircraft, intended to help United States Army and Navy anti-aircraft gunners refine their targeting skills.

In recent times, the word drone has become known for something far more lethal. After the attacks of September 2001, the United States deployed Predator pilotless aircraft against targets in Pakistan and Afghanistan as a key weapon in the struggle against terrorism.

But even during the D-Day summer of 1944, the Allies turned to high-stakes drone warfare. Under the code name Operation Aphrodite, radio-controlled bombers were packed with explosives and guided into the air by Allied pilots instructed to eject before their planes reached high-value targets in territory controlled by Nazi Germany. (Killed on one of these treacherous missions was the Navy aviator Lt. Joseph P. Kennedy Jr.)