What teenager Zubair Ur Rehman remembers most about the day his grandmother was killed is how "particularly blue" the sky was in the Pakistani tribal region of North Waziristan. Yes, just as New Yorkers say of 9/11.

The boy's beloved Mamana Bibi, the midwife in the village of Tappi, was just a few meters away in her garden, showing his younger sister, Nabila, how to tell when the okra is ready to be picked. "I was excited," he said of the upcoming Muslim holiday Eid al-Adha.

They all saw the drone hovering, Zubair said through an interpreter in his native Pashto, but that's not such an uncommon sight where they live, and "I didn't worry; why would I worry? Neither my grandmother nor I were militants."