Abu Bakr Baghdadi’s self-elevation to the caliphate reminds me of the last time someone declared himself caliph. It was 90 years ago, in March 1924, when the Hashemite ruler of Mecca, Hussein, had himself proclaimed caliph. He was a real descendent of the Prophet, but by the autumn the Saudis had given him the boot. To my knowledge, no one since has had the audacity to declare himself caliph. – Martin Kramer on Facebook.