For 250 years, Masood Akhundzada's family has protected Afghanistan's most sacred artifact: a cloak said to have been worn by the Prophet Muhammad. Its power drew Afghan kings and presidents and Taliban leaders to a small, blue shrine in a city conquered by Alexander the Great and contested ever since.

By the time Akhundzada inherited the guardianship in 2008, it was an honor that came at a high price. Five previous guardians — his father, brothers and cousins — had been assassinated, shot in their offices, in markets and airports. They were hunted, most believed, for their connection to a piece of Islamic history that the insurgency wanted desperately to reclaim.

When Akhundzada, a large man with a wild beard and an easy smile, accepted the keys to the shrine, he also bought a gun. There is no law, he said, that prevents a mullah from being armed if his life is in danger.