As I told the UN Security Council this spring, what inspires the most lethal assailants in the world today is not so much the Quran or religious teachings but rather a thrilling cause and a call to action that promises glory and esteem in the eyes of friends. Foreign volunteers for the Islamic State are often youth in transitional stages in their lives – immigrants, students, people between jobs and before finding their mates. Having left their homes, they seek new families of friends and fellow travellers to find purpose and significance.