For the enigmatic Baghdadi to have appointed himself as leader of the world’s Muslims and inheritor of al-Qaeda’s legacy is an act of extraordinary ambition. While bin Laden was raising money for the Afghan Mujahideen, Baghdadi was at primary school. Bin Laden electrified his followers with quietly intense rhetoric. Baghdadi has never publicly released a video. Like many caliphs before him, his authority is based on his shrewd military command, rather than the purity or novelty of a revolutionary message.

His challenge to al-Qaeda is, however, devastating. Zawahiri expelled IS from al‑Qaeda in February for rebelling against his authority. Now Baghdadi has thrown the gauntlet back at Zawahiri’s feet. And why not?

Zawahiri is a bespectacled and bookish theorist of jihad, hunkering down in Pakistan. Baghdadi, the would-be Caliph Ibrahim – much like the Pope, he gets a new name with the office – is a proven commander who has shattered the Iraqi army, historically one of the most powerful in the Arab world.

Neither Zawahiri nor his predecessor, Osama bin Laden, ever controlled territory.