At the same time, Baghdadi’s death could accelerate ISIS’s evolution from a militant group holding territory in the Middle East to an amorphous terrorist organization that could strike in any place at any time. Western leaders should pay close attention to the group’s response to this crisis, as it has the potential to increase the threat of terrorist attacks in their countries.

To understand how ISIS may respond to its leader’s death, consider how the group has previously responded to setbacks. Following the loss of large swathes of territory over the last few years, ISIS shifted its raison d’etre from holding territory to embarking upon an insurgency campaign. In the formative stages of the group, it operated in small cells, borne out of local grievances that were fused with the ideological worldview of a number of former members of al-Qaeda and the military guile of members of the Baathist regime.

Following allegations of Baghdadi’s demise, there has been a great deal of infighting among the rank-and-file ISIS members, which suggests that a leadership struggle has begun. Abu Haitham al-Obaidi, a prominent ISIS official in Hawija, has allegedly declared himself caliph. Obaidi has allegedly withdrawn from the group with a large number of followers. One imagines that without a charismatic leader to hold the group together, similar things will continue to happen. Such events will make it much harder for coalition forces to defeat ISIS on the ground.

We must also consider the impact on the group internationally—concerning both those committed to leaving their countries to join the group and those willing to commit violent acts across the West. Ultimately, the ideological message of the group will resonate long after Baghdadi’s death. In Dabiq, the group’s propaganda publication, senior ideologues have referred to a messianic vision of the End of Days, stemming from a war between ISIS and “the armies of Rome,” in a nod to the Crusades. This apocalyptic narrative is imperative in encouraging people to commit acts of terrorism across the world as we have seen in the UK, across Europe, and in the U.S.

Although a huge blow, Baghdadi’s death would feed into this narrative of an existential struggle. His message of certainty that has proved so compelling has certainly been damaged. The number of people joining ISIS from abroad will fall, undoubtedly, but this may result in people committing violent atrocities in their home countries instead. We must not think that this is the end of ISIS. It is perhaps instead the beginning of a different type of threat.

Baghdadi’s death may also serve to invigorate al-Qaeda, who had been marginalized by the emergence of ISIS in 2014. The latter’s combination of a fundamentalist message and the use of extreme violence appealed to many foreign fighters who would previously have traveled to join al-Qaeda. The organization has sought to reinvent itself in the years after ISIS’s emergence, condemning the group’s brutality and the sectarian violence that has become a key aspect of the ISIS agenda. With Baghdadi’s death, al-Qaeda may sense an opportunity to regain ground lost to ISIS in the struggle to be at the vanguard of the global jihadi movement. This could result in a range of attacks as different terrorist groups try to demonstrate their vitality and capabilities.

What has become abundantly clear is that whether dead or alive, Abu Bakr al-Baghdadi remains the Schrodinger’s Cat of the contemporary global jihadi movement. Simultaneously dead and alive, Baghdadi’s legacy remains and continues to shape terrorism across the world.

Simon Mabon is a lecturer in international relations at Lancaster University and co-author of The Origins of ISIS.