Thinking about the terrorists.
Muslim leaders reject ISIS's claim.
Muslim leaders reject Boko Haram's claim.
Yet terrorists are being recruited from mainstream Islamic communities in the United States as well as Europe. These people are eager to join the new caliphate.
Muslim scholars/leaders insist they can't form a caliphate. But they did.
It's kind of like the Reformation - Protestants formed their own catholic church - and today we want Christian unity. Perhaps it's similar to schism? Fundamentalist reform? Heresy? It doesn't change the reality - they exist.
Abu Bakr al-Baghdadi and Boko Haram* call it a caliphate and will behead anyone who disagrees.
*It's what they do: Boko Haram has targeted Christians in areas the group controls in Nigeria, reportedly beheading all Christian men and forcing the widows into sexual slavery.