A disembodied voice sounded over a loudspeaker. "Incoming. Take cover," it warned to anyone within earshot. Then, the sirens began to wail. Erin Delaney assumed it was a drill. She peeked down the hallway to see how other people were responding. Then she hit the deck. It was not a drill. The NATO base in Kabul where Delaney had been working for weeks was being attacked. Delaney, 24, had never had any military training.

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