ISIS has released video of its leader Abu Baqr al Baghdadi appearing at a Mosul mosque (pictured) during Friday prayers last week, claiming to be the caliph, or leader, of the Muslim faithful and calling himself Caliph Ibrahim.

Carrying the supposed moniker of 'the invisible sheikh' is great for one's mystique but putative caliphs need to actually be seen. The staged video was designed to not only make sure that Baghdadi remains in the news, but that he is seen as being religiously qualified as well as a military commander. Given the wide media coverage of the appearance, the ISIS marketing team has to be congratulated for the way it is positioning the brand.

But the first rule of marketing is that people need to be attracted enough to the product to buy it. And one of the intriguing things about Abu Baqr al Baghdadi's proclamation of a caliphate and his re-branding as Caliph Ibrahim is the degree to which anybody outside ISIS buys it. On that measure, his claim to leadership of the Islamic world is off to a slow start.

High profile clerics have failed to embrace his vision and, while they may have their own political (rather than purely scholarly) reasons for doing this, their opinions do carry weight.

For instance, the influential Jordanian Salafist ideologue Sheikh Abu Muhammad al Maqdisi, recently released from jail, praises ISIS's military victories but voices concerns about Baghdadi's ideological grab for power and has referred to ISIS as 'deviant'. Sheikh Yusuf Qaradawi, while welcoming the coming of the caliphate in the future, dismissed Baghdadi's claim to lead it, saying that only the entire Muslim nation could confer the title of caliph and that Baghdadi's claim was voided by shari'a law. The pro-caliphate Hizb ut Tahrir also repudiated Baghdadi's claim.

Baghdadi probably understands that, as a relative outsider, he will never win the loyalty of the professional clerical class. But another key performance indicator is whether other militant groups are pledging loyalty to ISIS. In the opaque and shifting world of jihadist groups it is hard to determine exactly who owes loyalty to whom, as oaths of allegiance are always be made publicly and groups are liable to splinter for a variety of reasons. But even here the results are relatively disappointing for ISIS. Outside of ISIS itself, the supporters of Caliph Ibrahim at present include a small group of Pakistani Taliban, perhaps an element of al Qaeda in the Islamic Maghrib (or perhaps not), a branch of Ansar al Sharia in Yemen (and, if Twitter is to be believed, another branch in Tunisia as well), and allegedly the Egyptian group Ansar Bayt al Maqdisi. Some ISIS wannabes such as the unknown Free Sunnis of Baalbek also claim to have thrown in their lot with the new caliph. Indonesian groups have supposedly done the same.  

ISIS has not drawn away key al Qaeda franchisees or complete elements of the armed Syrian opposition, so Baghdadi's caliphate remains aspirational.

ISIS has certainly gained kudos and headlines through its military success but its dominance in parts of Iraq is aided by political gridlock in Baghdad and Iraqi military ineffectiveness. Neither of these will last forever and Baghdadi's forces will at some stage be engaged in decisive fighting in Iraq, at which point his tactical alliance with the tribes will come under enormous pressure. He needs to maintain military momentum, and he has been attempting to do this in eastern Syria. How long he can maintain his cross-border empire remains to be seen, but it will in all likelihood remain an ephemeral construct.

Baghdadi's caliphate claim has shown how diffuse, splintered and broadly-based the regional Islamist threat has become and how easily groups can be swayed by martial success. Even though ISIS's success, and its caliphate, will not last forever, in the idealised worldview of radical islamists it will serve as a model of what can be done by committed and observant Muslims.

The Afghan Arabs under bin Laden had to shelter in non-Arab lands and were constantly under threat. Baghdadi by contrast has achieved what nobody among contemporary jihadists has before him: he has carved out a piece of the historical Arab world, defeated the 'kafir', done away with the Western-imposed borders and placed his territory under Islamic rule. Even if few people physically join his caliphate and it lasts only weeks or months, the damage may have been done.