Overcoming differences might be easier if personal animosity were the only obstacle separating al Qaeda and the Islamic State, especially if one or more of the warring personalities were killed. Even if Jabhat al-Nusra and the Islamic State were not fighting each other in Syria and al Qaeda and Islamic State franchises were not fighting elsewhere, the groups’ conflicting ideologies would make broad reconciliation difficult. This is especially clear because the two groups have gone to such lengths to outline their differences. Explaining a merger with a group previously labeled as apostates or kharijites would be an awkward and difficult task for the leaders of both groups.
Ideology is just too important for al Qaeda and for the Islamic State. Indeed, members of both groups are willing to die for their beliefs. While some claim that jihadist leaders cynically use religion to manipulate others, their actions keep with their extremist beliefs, indicating their sincerity. Because both groups claim to have exclusive understanding of the correct interpretation of Islam regarding jihad, they are unlikely to merge. Additionally, after proclaiming itself to be the global leader of all Muslims, allowing itself to become subordinate to another group would be insupportable for the Islamic State.
While al Qaeda is down, it is clearly not out, and the group’s Yemen franchise has made tremendous gains since the Saudi-led air campaign began degrading its most dangerous enemies there. Additionally, taking Idlib, alongside ally Ahrar al-Sham, highlighted Jabhat al-Nusra’s strength in Syria.