The issue of imminence is similarly fuzzy. Government attorneys stretched the definition from “about to happen” to something much broader. According to the Justice Department white paper, an individual doesn’t have to be on the verge of attacking, or even in the midst of a particular plot, to be a legitimate target. A person could be an imminent threat solely by virtue of being labeled a “senior operational leader,” someone whom the U.S. believes is actively planning to kill Americans. In other words, once someone is identified that way, he is deemed an imminent threat and, as such, a fair target.

According to U.S. intelligence, Qadhi was a senior operational leader in al-Qaeda who met both requirements for lawful killing: he was an imminent threat, and he couldn’t be captured. Yemeni intelligence was less certain. After all, the Yemenis had captured Qadhi once before, when they arrested him in 2008. And in January 2012, he had been part of a tribal mediation team sent at the behest of the government to negotiate with al-Qaeda fighters who had taken control of a city fewer than 100 miles south of Sanaa. Besides, Qadhi wasn’t hiding in the mountains with the rest of al-Qaeda—he was living in his house in Bayt al-Ahmar, a stone’s throw from former President Salih’s hilltop palace.

Still, when the U.S. asked the Yemenis for permission to strike, the government agreed. Some officials even concurred with the American assessment that Qadhi was al-Qaeda’s local commander in Bayt al-Ahmar, pointing to the fact that he had a giant mural of the black flag associated with al-Qaeda painted on his house. But according to one Yemeni official who reviewed the intelligence, others argued that Qadhi was a recruiter for al-Qaeda, not a senior operational leader. Whatever Qadhi’s ties to al-Qaeda, one thing was clear: he had yet to carry out an attack. Thus, any strike against him would by definition be a preemptive one.

According to the video confession, when Barq’s father dropped him off back in Bayt al-Ahmar, the young spy did what the officers in the Republican Guard had instructed during their evening meeting. He reestablished contact with Qadhi, his surrogate father in the village, and waited. On Wednesday, October 31, when Qadhi went to the bathroom, the boy made his move.

“I climbed on the table where his coat was and put [a tracking chip] in his pocket,” Barq says. Scrambling to complete his mission before Qadhi came out of the bathroom, he slipped back to the floor and slid a second chip under a freestanding cupboard, just as he had been taught.

Later that day, apparently worried that the chip under the cupboard was too obvious, Barq removed it. But the first chip, the one in the pocket of Qadhi’s coat, was still in place and emitting a signal.

Neither the boy nor the man who had taken him in off the street could have known it yet, but by that point, Adnan al-Qadhi was effectively dead. All that was left was for a drone operator to push a button that would fire a missile.

In the United States, the presidential election was entering the home stretch. While President Obama and Mitt Romney stumped for last-minute votes, drones from a secret base in either Saudi Arabia or Djibouti followed Qadhi’s every move. As soon as Qadhi put on his coat and U.S. forces got a lock on him, it didn’t matter whether he found the electronic tracking chip or even whether he never wore his coat again. He had been marked. (Chips like this are supposed to help ensure that drone strikes hit only the target sought, and not a civilian who happens to be in the same location.)