Members of al Qaeda's Nusra Front carry their weapons as they move towards their positions during an offensive to take control of the northwestern city of Ariha, May 28, 2015.
Ammar Abdullah / Reuters

Last month’s announcement of the death of the Taliban leader Mullah Omar occasioned a barrage of commentary about the implications for the Taliban and the ongoing Afghan peace talks. But his final departure from the scene could have a momentous impact on the jihadi movement as well, strengthening ISIS and further diminishing al Qaeda.

The reclusive Omar was a strong ally of al Qaeda, and his passing is a major blow to the group and its leader, Ayman al-Zawahiri. Omar had been a loyal friend to al Qaeda since the Taliban took control of Afghanistan in 1996. In those years, he stood by Osama bin Laden even as the al Qaeda chief defied his orders to stop giving interviews to Western media, which were complicating the Taliban’s efforts to normalize relations with the international community. Omar’s loyalty to bin Laden even caused discord within the Taliban; one faction wanted Omar to cut ties with the uncontrollable Saudi. The costs of protecting bin Laden and his followers mounted still further after 9/11, when Omar refused to hand over bin Laden, leading to the U.S. invasion that toppled the Taliban regime.

A member of al Qaeda's Nusra Front climbs a pole where a Nusra flag was raised at a central square in the northwestern city of Ariha, after a coalition of insurgent groups seized the area in Idlib province, May 29, 2015.
A member of al Qaeda's Nusra Front climbs a pole where a Nusra flag was raised at a central square in the northwestern city of Ariha, after a coalition of insurgent groups seized the area in Idlib province, May 29, 2015.
Khalil Ashawi / Reuters
Al Qaeda’s approach toward the Taliban was more utilitarian. In 1998, bin Laden pledged allegiance to Omar, reluctantly and through a proxy rather than in person. It was an effort to assuage the Taliban’s anger about al Qaeda defying Omar’s instructions to lower its profile and avoid doing anything that harmed Afghanistan’s interests. In subsequent years, al Qaeda continued to view the pledge (Bay’a) through a pragmatic lens, shifting the way it used the oath to suit its own interests. After the Islamic State (also called ISIS) began its rise, al Qaeda found the pledge a useful tool for thwarting its former branch.

Still reeling from the death of bin Laden and other senior leaders, and grasping for a response to the events of the Arab Spring, al Qaeda didn’t have much power to counter ISIS. It was too weak to discipline its Iraqi branch by force. So instead, al Qaeda chose to disavow the group, only to see ISIS’ power continue to grow a few months later when it captured Mosul and gained control over large swaths of Iraq and Syria. When ISIS followed its success by announcing the revival of the caliphate, with its leader Abu Bakr al-Baghdadi as the new caliph, al Qaeda remembered its old friend, the Taliban. In an effort to resist ISIS encroachment and to challenge the legitimacy of the self-styled caliphate, Zawahiri renewed the Bay’a to Omar. The leaders of al Qaeda’s branches followed suit, reiterating their allegiance to Zawahiri and, through him, to the Taliban leader.

Omar’s death makes al Qaeda more vulnerable to ISIS’ demand that it—along with Muslims everywhere—recognize Baghdadi’s authority.
Al Qaeda’s logic was simple. First, it wished to challenge ISIS’ claim to represent all Muslims by reminding jihadis and their sympathizers worldwide that Omar had assumed the title of the Emir of the Faithful years before Baghdadi. The Taliban presented itself as only an emirate, a much less ambitious claim than calling itself a caliphate, but Omar’s title was sufficient to suggest that ISIS’ authority was contested. Second, by reiterating its ties to the Taliban, al Qaeda sought to fend off ISIS demands that it submit to the self-styled caliph. Third, al Qaeda tried to distinguish itself from ISIS by signaling that it adheres to its commitments. Baghdadi, in contrast, reneged on his oath to Zawahiri. Finally, by reaffirming Bay’a, Zawahiri suggested that al Qaeda was focused on pleasing God and acting for the good of the Muslim community, whereas Baghdadi was seeking personal power.

Now that Omar’s death has been announced, al Qaeda’s strategy could crumble. At the very least, it makes al Qaeda more vulnerable to ISIS’ demand that it—along with Muslims everywhere—recognize Baghdadi’s authority. Al Qaeda’s allegiance to Omar does not transfer automatically to his successor. In theory, Qaeda could reassess the situation and shift its allegiance to ISIS, but it is highly unlikely that Zawahiri would ever agree to subordinate himself to al Qaeda’s former branch. At the same time, defending a decision to stick with the Taliban is going to be more difficult. Omar has been replaced by a considerably less well regarded leader, and the succession process exposed some major internal rifts within the Taliban.

Supporters of the religious party Jamiat Nazariyati pray for the late Taliban leader, Mullah Muhammad Omar, in Quetta, Pakistan, August 2, 2015.
Supporters of the religious party Jamiat Nazariyati pray for the late Taliban leader, Mullah Muhammad Omar, in Quetta, Pakistan, August 2, 2015. 
Naseer Ahmed / Reuters
Zawahiri had been quite successful at keeping other al Qaeda branches loyal to him during ISIS’ meteoric rise. Although the group has suffered from defections to ISIS, primarily from rank-and-file and mid-level operatives, most leaders have continued to stand by Zawahiri. Even when the leaders of al Qaeda’s franchises in Yemen and Somalia died in drone strikes, their successors remained loyal to central command. But Omar’s death is likely to intensify pressure from members to join hands with ISIS. The reports that the Taliban kept Omar’s death a secret for two years (denied by the Taliban) undermine the militant group’s credibility and bolster ISIS’ allegations that the Afghanistan-based group suffers from religious deficiencies; after all, if Omar indeed died long ago, the Taliban was led for two years by a figure who was not nominated through a legitimate Islamic procedure. True or not, the doubts regarding the timing of Omar’s death will weaken al Qaeda’s ability to use the Taliban as a counterweight to ISIS and are bound to lead to a wave of defections to ISIS. The longer it takes for Omar’s successor, Mullah Akhtar Muhammad Mansour, to unite the Taliban around his leadership, the harder it will be for al Qaeda to contain the fallout.

ISIS is likely to continue to use the gap between the reported date of Omar’s passing and the Taliban’s announcement to intensify doubts about Zawahiri. If Omar has been dead for two years, the question of what Zawahiri knew is bound to come up. On the one hand, it is possible that he knew about the death of the Taliban leader, but could not divulge the information in deference to the Taliban’s leadership. But if that was the case, al Qaeda’s effort to use the authority of a dead man to delegitimize the Baghdadi’s self-styled caliphate makes it complicit in the Taliban’s deceit. On the other hand, if he did not know that the Taliban leader was dead, Zawahiri could be exposed as uninformed, making it evident that al Qaeda’s influence in Afghanistan and Pakistan has been greatly diminished. Thus, unless evidence is produced that Omar has only very recently died, Zawahiri will come under attack for ignorance, poor judgment, or both. Either way, his leadership has suffered a major hit.

The ability of al Qaeda’s leader to preserve the organization will be further limited by threats to his own survival. Zawahiri has not been heard from since September 2014 when he introduced AQIS, al Qaeda’s newest branch in the Indian subcontinent. He has become increasingly dependent on al Qaeda’s franchises in Yemen and Syria to keep the organization afloat. Already under pressure, Zawahiri has to worry about ISIS loyalists on the ground even as he continues to watch for U.S. drones above. After all, for ISIS, capturing the al Qaeda chief could be a game-changer.

Al Qaeda’s misfortune is ISIS’ good luck. The group’s leaders can celebrate not only weakening the opposition to its expansion in Afghanistan and Pakistan, but also the boosting of its claims for leadership of the jihadi movement. Although the demise of the Taliban leader is unlikely to strengthen ISIS’ authority over all Muslims, the group no doubt sees Omar’s death as another positive omen that its caliphate is here to stay.

  • BARAK MENDELSOHN is Associate Professor of Political Science at Haverford College and a Senior Fellow at the Foreign Policy Research Institute.
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