Kayla Mueller was a 26-year-old aid worker from Prescott, Arizona. She was not a thrill-seeker. She was the kind of person drawn toward suffering with a medical bag and a stubborn belief that people ...

They came from around the world, four women drawn to the Islamic State group's "caliphate." They said it was out of misguided religious faith or naivety or youthful rebellion, but whatever the reason, ...