Abstract: After Taliban emir Mullah Mansoor was killed in a U.S. drone strike on May 21, one key question is whether al-Qa`ida leader Ayman al-Zawahiri will pledge allegiance to his successor. When al-Zawahiri pledged allegiance (bay`a) to Mansoor last summer, some observers were puzzled. Instead of laying claim to the title of emir al-mu’minin (commander of the faithful) and directly challenging Abu Bakr al-Baghdadi for leadership of the global jihadist movement, al-Zawahiri exposed himself to ridicule by subordinating himself to a man whose succession to Mullah Omar was opposed initially by significant factions of the Taliban movement. But at a time of rising competition from the Islamic State, al-Zawahiri arguably had little choice. His decision was consistent with strategic maxims that have defined his career, including forging and maintaining alliances to offset weakness. Nine months later, with the Taliban surging in Afghanistan and al-Qa`ida riding its coattails, his decision appears to be paying dividends, and he is likely to pledge bay`a to Mansoor’s successor, Mullah Haibatullah Akhunzada.
When al-Qa`ida leader Ayman al-Zawahiri, the 64-year-old veteran of global jihad and the haughty scion of an ‘aristocratic’ Egyptian family, subordinated himself on August 13, 2015, to a Pashtun tribesman at least 10 years his junior by pledging bay`a to the new emir of the Afghan Taliban, Mullah Akhtar Mohammad Mansoor, it must have been a bitter pill to swallow. Rather than assume the mantle of emir al-mu’minin (commander of the faithful) and directly challenge Abu Bakr al-Baghdadi for leadership of the global jihadist movement, al-Zawahiri opted to play second fiddle to a man whose succession to Mullah Omar was opposed by significant factions of his own Taliban movement, some of whom depicted Mansoor as a pawn of Pakistan’s intelligence services.
Accentuating the irony, al-Zawahiri had initially opposed Usama bin Ladin’s pledge of allegiance to Mullah Omar two decades previously, if we are to trust the account given by Egyptian jihadi Mustaf Hamid (better known as Abu’l-Walid al-Masri). More doctrinally oriented and ideologically rigid than bin Ladin, al-Zawahiri appears to have believed the Taliban were too deviant in doctrine. A survey conducted by jihadis in Afghanistan in the late 1980s shows that members of al-Zawahiri’s Egyptian Islamic Jihad believed “nothing is to be hoped for from the war in Afghanistan, nor will there arise an Islamic State there, on account of doctrinal/ideological defects among the leaders and the masses.”
This article argues that in the summer of 2015 with the Islamic State threatening to eclipse al-Qa`ida as the standard-bearer of global jihad, al-Zawahiri had little choice but to nail his colors to the Taliban mast. It argues his decision was consistent with strategic maxims that have defined his career, including forging and maintaining alliances to offset weaknesses. And finally it will document how, despite exposing himself to ridicule from Islamic State supporters after Mullah Mansoor’s leadership got off to a shaky start, his decision paid dividends as Mansoor consolidated his position and the Taliban started surging in Afghanistan. For those reasons, after Mansoor was killed on May 21 in a U.S. drone strike in Balochistan, al-Zawahiri is likely to swear fealty to his successor, despite the risk of new convulsions within the Taliban after they announce a new leader.
When it became known that Mullah Omar was dead and Mullah Mansoor was elected as his successor in July 2015, al-Zawahiri and the al-Qa`ida network were placed in a quandary. The al-Qa`ida leader was under pressure to make a decision that would enable his organization to once again appear relevant in the eyes of the world’s jihadis.
Just a year after establishing its caliphate, the Islamic State seemed poised to eclipse al-Qa`ida as the world’s dominant jihadi movement, and without the charismatic and authoritative leadership of bin Ladin, al-Qa`ida risked being sidelined. Al-Zawahiri’s passive approach to the controversy caused by the rift between Abu Bakr al-Baghdadi and Abu Muhammad al-Julani that eventually led to the split and the creation of Jabhat al-Nusra left the impression of al-Qa`ida’s paramount emir as a leader without much authority. Analysts and jihadis alike started to talk about al-Zawahiri’s irrelevance and hence, the election of Mullah Mansoor both presented al-Zawahiri with a risk and an opportunity. Should he play it safe and continue to play second fiddle to a new Taliban emir, or should he seize the opportunity and challenge the global rise of the Islamic State and al-Baghdadi even if that meant losing the support of the Taliban and hurting its position in Afghanistan and Pakistan?
To many in the jihadist fold, al-Zawahiri’s decision to pledge allegiance to Mullah Mansoor confirmed the general impression of him as an old man growing increasingly irrelevant, out-of-sync, and lacking in the courage to confront the Islamic State. But above all it exposed the fragility of al-Qa`ida’s position. Al-Zawahiri arguably had little choice but to subordinate himself to Mansoor and maintain the Taliban alliance. As Barak Mendelsohn has noted, al-Qa`ida and al-Zawahiri’s alliances have often been sought out of weakness rather than of strength.
Bin Ladin’s Bay`a
Bin Ladin’s original bay`a to Mullah Omar had also been borne of necessity. In 1999 when bin Ladin finally decided to pledge allegiance to Mullah Omar he did so because he assessed that it was the best strategic option rather than for any ideological or doctrinal reasons.[a] Al-Qa`ida, having been displaced from Sudan, was without a sanctuary and so allying with the Taliban made sense in order to receive shelter in the Islamic Emirate of Afghanistan and to consolidate its position among a myriad of competing militant groups operating in Afghanistan at the time.[b] Relocating back to Afghanistan after a brief period in Saudi Arabia and then Sudan, bin Ladin was in need of local support to continue his global jihad project. Being on friendly terms with the Taliban, which was governing Afghanistan, was imperative in these efforts. Vahid Brown argues that bin Ladin’s pledge was “a calculated political move” and “a strategy of expediency,” thus highlighting bin Ladin’s weak negotiating position. He needed the Taliban more than they needed him.
The original bay`a from bin Ladin to Mullah Omar has always been shrouded in mystery. No footage exists of the event and neither bin Ladin nor Mullah Omar issued any communication on the matter. Apparently it seems that after a long period of contemplation, in 1999 bin Ladin decided to pledge allegiance to Mullah Omar via proxy, namely the Egyptian jihadi Abu’l-Walid al-Masri, who was close to the Taliban. Despite all the uncertainty about what actually happened, it is known that bin Ladin’s pledge of allegiance was what jihadis refer to as a “greater bay`a,”[c] which he himself confirmed on several occasions.[d] The bay`a effectively placed the al-Qa`ida founder below Mullah Omar in the global jihadist hierarchy.
Al-Zawahiri’s Strategic Rationale
Although the context was very different in the summer of 2015, al-Zawahiri, like bin Ladin, found himself in a dependent position with the Taliban because of the rise of the Islamic State. Despite his initial disdain for the Taliban, years living in the region had softened his attitude. By the late 2000s with a Taliban insurgency gaining ground, Afghanistan had become a key focus of al-Zawahiri’s public statements, and soon after he assumed the top job in al-Qa`ida in 2011, al-Zawahiri himself pledged bay`a to Mullah Omar.[e]
At a time when the Islamic State was threatening to eclipse al-Qa`ida in the Arab world, the Afghanistan-Pakistan region was one of the few geographic areas where al-Qa`ida retained primacy in the contest between the two groups, despite a nascent challenge from a group calling itself the Islamic State in Khorasan. For al-Zawahiri, refusing to pledge loyalty to Mansoor would have been to put all that at risk and potentially to lose out on significant future opportunities. Despite its damaged credibility because of the debacle of the cover up of Mullah Omar’s death, the Taliban had been gaining ground steadily in Afghanistan for a number of years and last summer were poised to make additional gains as international forces further scaled back their presence.
On a broader level, al-Zawahiri’s decision to pledge allegiance to Mansoor fits a general strategy al-Zawahiri has pursued for decades that is characterized by three priorities: seizing territory as a staging point for further expansion, winning the support of the Muslim masses, and jihadist bridge-building. After what appears to have been his initial disdain for Afghans, his public statements since 9/11 make clear he has come to see the Taliban as a vehicle for realizing all three of his strategic priorities in Afghanistan and Pakistan. The importance of forging alliances for al-Zawahiri became evident in the 1990s with his cooperation with bin Ladin in Sudan and his overtures to the Saudi jihadi commander in Chechnya Ibn al-Khattab. Later he signed the World Islamic Front fatwa with bin Ladin, while more recent examples include his welcoming in 2006 of the Algerian terrorist group GSPC into the fold as a fully fledged al-Qa`ida affiliate (AQIM), accepting the bay`a from al-Shabaab in 2012, and Jabhat al-Nusra’s strategy entering into military coalitions in Syria alongside more moderate factions.
Though it fit al-Zawahiri’s strategic rationale, embracing Mansoor also had major risks. When he declared his fealty to Mansoor, some analysts argued the pledge “might be a large step toward AQ’s demise.” This was in no small part because of the catastrophic way Mullah Omar’s death was handled by the Taliban and questions about the legitimacy of Mullah Mansoor.
Despite recent Taliban efforts to play up his jihadi credentials, Mansoor is not known for his exploits on the battlefield. Although he fought the Russians in the 1980s, since then he has been mainly seen as a political figure within the Taliban occupying positions as a minister before 9/11 and then as the shadow governor of Kandahar Province.[f] Mansoor’s slow start in gaining support from his own Taliban movement must thus have been a great concern for al-Zawahiri. In the months after Mansoor’s appointment several important Taliban figures and splinter groups attacked his authority. Not only did Mansoor initially fail to get the support of the family of Mullah Omar,[g] he was also criticized by senior Taliban leaders, most importantly by Mullah Qayum Zakir, an influential senior military commander who has been working actively against Mansoor’s efforts to crackdown on internal critiques. Zakir was supported in opposition to Mansoor when a group of approximately three dozen religious leaders in Quetta wrote a letter explicitly refuting the authority of Mullah Mansoor. Less surprising, the former Taliban commander Mullah Mansour Dadullah, who was expelled from the Taliban in 2007 but remained a popular figure within the broader movement, made clear his opposition to the new Taliban emir. Perhaps due to his criticism or because he was flirting with the Islamic State, Dadullah was killed in November 2015 in a gunfight with Taliban fighters in Zabul’s Khak-e-Afghan district. The Tehrik-e-Taliban Pakistan, popularly referred to as the Pakistani Taliban, has also declined to pledge allegiance to Mansoor, although this was not considered a necessity by Afghan Taliban leaders as the groups are separate entities.
The al-Qa`ida leader’s bay`a to Mansoor also presented the Islamic State and its followers with a new platform to ridicule al-Zawahiri. After splitting from al-Qa`ida on February 3, 2014, the Islamic State had generally sought to delegitimize al-Zawahiri, arguing that he was growing increasingly irrelevant, that he deviated from the path of bin Ladin, and that he is not fit to lead the global jihadist movement. But they had generally held off from criticizing the popular Mullah Omar and the Taliban. For example, in 2011 Abu Muhammad al-‘Adnani, then spokesperson of the Islamic State in Iraq (now the Islamic State), praised both the Taliban and the leadership of Mullah Omar.
But when the Taliban confirmed the death of Mullah Omar, the Islamic State went for the jugular. Since then, on the pages of Dabiq and Dar al-Islam magazines, it has depicted the Taliban as a nationalist movement that aims to obtain power within the territory of Afghanistan, which does not fit well with the salafi rejection of modern state boundaries or their focus on the global ummah. Mansoor is targeted for how he kept the death of Mullah Omar a secret for two years while publishing statements and speeches in the former Taliban leader’s name, while al-Zawahiri is ridiculed for giving bay`a to a person whose authority is not only contested within his own movement but who is also considered to be collaborating with the Pakistani intelligence service, ISI. Al-Zawahiri also received criticism for the fact that al-Qa`ida renewed its allegiance to Mullah Omar in 2014, the year after he had died as it turned out. In one of the sharpest attacks, the leader of Islamic State in Khorasan, Hafidh Said Khan condemned the ideology of the Taliban and the behavior of Mansoor while claiming that Mansoor’s leadership had caused a mass exodus of Taliban fighters to the Islamic State.
In interviews the authors conducted with Islamic State members, the impression was that al-Zawahiri’s bay`a to Mansoor has been considered a complete joke. Not only do Islamic State members portray Mansoor as in the pocket of Pakistan’s ISI, but they also claim that he is collaborating with the Iranian intelligence service and that the bay`a can only be interpreted as a sign of desperation. To add insult to injury there has been gleeful circulation among credulous Islamic State supporters of an audio tape allegedly dating back to 2007 in which Mullah Omar refers to Mullah Mansoor as not being fit to lead the Taliban, despite all the indications that Mullah Omar was referring to a different Mansoor.[h]
Despite being a bitter pill to swallow, al-Zawahiri’s bay`a produced an increasingly bountiful harvest. Three developments provided him with a degree of vindication. First, after the initial turbulence, Mullah Mansoor managed to consolidate internal support by bribing senior commanders or appointing them to central positions. At the time of his death, that support included Mullah Omar’s family as his son and brother recently joined the Taliban’s leadership council.
Second, the Taliban insurgency is currently on the rise in Afghanistan as international forces are leaving the country, bolstering Mansoor before he was killed and allowing al-Qa`ida to ride the Taliban’s coattails as they expand their presence in Afghanistan. Last year the Taliban managed to take over and hold the northern provincial capital of Kunduz for a few weeks, and it recently launched its spring offensive, titled “Omari,” which started off with a devastating suicide attack in Kabul. The rising fortunes of the Taliban has facilitated a significant comeback for al-Qa`ida in the region, leading an Afghani defense official to claim that al-Qa`ida is once again “very active” while U.S. Major General Jeff Buchanan argues that al-Qa`ida has more fighters than earlier estimated and has managed to establish several training camps in area under Taliban control. In one camp alone, U.S. forces found more than 150 al-Qa`ida fighters.
Third, the al-Qa`ida-Taliban alliance was strengthened under Mansoor. According to U.S. General John Nicholson, Mullah Mansoor’s legitimacy gap initially forced him to move closer to groups like al-Qa`ida. This was evidenced in Mansoor’s effusive praise for al-Zawahiri in response to the various groups that pledged bay`a. “I first and foremost accept the pledge of allegiance of the esteemed Dr. Ayman ad-Dhawahiri [al-Zawahiri], the leader of international Jihadi organization (Qaedatul Jihad).” Furthermore, in a move to consolidate his power, Mansoor appointed Sirajuddin Haqqani, the son of Jalaluddin Haqqani, as one of his two deputies. Sirajuddin is known to be very close to al-Qa`ida and, according to U.S. intelligence sources, even to be on al-Qa`ida’s Shura Council.
These developments have enabled al-Qa`ida to build up a stronger presence in Afghanistan and have allowed al-Zawahiri to pursue his long-term strategy of building up mass support and a territorial base for the future expansion of jihad. But al-Zawahiri also got lucky. The situation now would have been rather different had Mansoor failed to consolidate power. To argue that al-Zawahiri knew how things would turn out would probably be giving him too much credit. This opinion is certainly shared within the Islamic State and among its supporters, who continue to discredit the al-Qa`ida leader.
It should also be noted that, to date, al-Zawahiri’s bay`a has not been supported explicitly by the leaders of any of al-Qa`ida’s affiliates, who have remained quiet on the issue with only individual al-Qa`ida members, like al-Qa`ida official Hussam Abdul Raouf, following al-Zawahiri’s lead and pledging allegiance to the Taliban leader.
Despite the overall positives for al-Zawahiri in pledging allegiance to Mansoor, the latter’s death was also a reminder of the vulnerability of al-Zawahiri’s position. To a significant degree, his decision to pledge bay`a to Mansoor last summer locked him in to pledging the same oath to any successor, despite the risk that there could be a new power struggle within the Taliban that might jeopardize its gains in Afghanistan and open the door once again to the Islamic State. Given that his pledge to Mansoor paid dividends, al-Zawahiri is likely to move quickly to swear bay`a to his successor, Mullah Haibatullah Akhunzada, who was elected as the new leader on May 25. Although Haibatullah always was the likely candidate, both Sirajuddin Haqqani, the other deputy leader under Mansoor, and Mullah Omar’s son Mullah Mohammed Yaqoob were mentioned as potential candidates. To build on Mansoor’s efforts of unifying the Taliban movement, Haqqani and Yaqoob have been elected new deputies in a move that favors not only the powerful Haqqani network but also Mullah Omar’s family and the Kandahari faction of the Taliban. The Taliban choice for stability is important for al-Zawahiri as it minimizes the risks of divisions and damaging repercussions for al-Qa`ida.
Pledging allegiance to Mullah Mansoor was arguably the least bad choice al-Zawahiri could make in the summer of 2015 given the mounting challenge from the Islamic State and the need for every ally he could get to maintain al-Qa`ida’s standing in the global jihadist movement. And while it led to heated criticism in the short-term, it is now paying dividends.
With the Islamic State seizing the initiative in many parts of the Arab world, Afghanistan and Pakistan remain one of the few regions in the world where al-Qa`ida retains primacy, and al-Zawahiri likely believes it is imperative to maintain this as part of a longer-term effort to roll back Islamic State influence worldwide. He is likely, therefore, to swear bay`a to Mullah Haibatullah. While the Islamic State has built up a nascent presence in Afghanistan, in recent months the Taliban appears to have contained and even reversed the gains made by the rival group.
With the Taliban growing ever stronger in Afghanistan as it exploits the void left by retreating international forces, al-Zawahiri likely believes al-Qa`ida has an opportunity to expand significantly its presence in the country as a new territorial base from which to challenge the Islamic State. There has been growing evidence of al-Qa`ida restoring a presence in Afghanistan, including the building up of operations by Farouq al-Qahtani in Nuristan and Kunar provinces and the establishment of a sprawling camp complex near Kandahar, which was dismantled last October.
Tore Hamming is a Ph.D. candidate at the European University Institute studying inter-movement dynamics within Sunni jihadism with a special focus on the al-Qa`ida-Islamic State relationship. Follow @Torerhamming
Olivier Roy is a professor at the European University Institute and the author of Globalized Islam. He previously headed the OSCE’s Mission for Tajikistan and was a consultant for the U.N. Office of the Coordinator for Afghanistan.
The authors wish to thank Paul Cruickshank for his considerable editorial input with this article.
[a] Ideologically, the Taliban and al-Qa`ida differ as the former is nationalist focused whereas the latter engages in global jihad. When it comes to religious doctrine, the mainly Deobandi (and tribal-influenced) Taliban follow the Hanafi school of fiqh and are considered less strict, or purist, than the salafi-dominated al-Qa`ida.
[b] This strategic political reason indeed sounds plausible considering how Deobandi doctrine and Hanafi fiqh are generally perceived negatively within the jihadi-salafi current.
[c] Pledges of allegiance, or bay`a, play an important role within the jihadi milieu. Formally, it is about giving and obtaining authority. However, as is evident in the al-Qa`ida-Taliban relationship, pledges of allegiance are often the result of strategic decisions. Jihadis work with three categories of bay`a: the greater bay`a (bay’at al-uzma), the smaller bay`a (bay’at ‘amma), and the war bay`a (bay’at harb). The difference between the three types pertains to the scope of authority given to a leader. Another and more pragmatic way of viewing the bay`a is proposed by Abu Ja’far al-Hattab, a Tunisian former sharia council member of Ansar al-Shariah, who now has allegedly shifted sides to the Islamic State. Al-Hattab defines two types of bay`a, one being ‘restricted’ and the other ‘unrestricted.’ The restricted bay`a is given to the leader of a militant group, its terms are limited geographically and obligates obedience only in relation to jihad. This resembles something in between the smaller bay`a and the war bay`a. The unrestricted bay`a is given to the head of a political community—an emir or caliph—and its terms are unlimited, obligating obedience in all matters. An unrestricted bay`a is similar to the greater bay`a.
[d] In June 2001, Usama bin Ladin again spoke about his pledge to Mullah Omar, confirming it was a “greater pledge” (bay’a ‘uzma). Anne Stenersen and Philipp Holtmann, “The Three Functions of UBL’s ‘Greater Pledge’ to Mullah Omar (2001-2006-2014),” Jihadology.net, January 8, 2015.
[e] In his obituary for bin Ladin, al-Zawahiri says, “We renew the oath of allegiance to the Amir of Believers Mulla Muhammad Omar Mujahid, may Allah protect him, and we promise him to hear and obey, in bad and good times, and on Jihad for the cause of Allah and establishing Sharia and supporting the oppressed.” See Ayman al-Zawahiri, “And the Noble Knight Dismounts,” June 8, 2011.
[f] The Taliban published a 5,000-word biography on Mullah Akhtar Mansoor. Taliban, “Introduction of the newly appointed leader of Islamic Emirate, Mullah Akhtar Mohammad (Mansur), may Allah safeguard him),” September 2015.
[g] Mullah Omar’s eldest son, Mullah Yaqoub, and his brother, Mullah Manan, were initially opposed to the leadership of Mullah Mansoor. See Saleem Mehsud, “Kunduz Breakthrough Bolsters Mullah Mansoor as Taliban Leader,” CTC Sentinel 8:10 (2015).
[h] Al-Qa`ida and Taliban followers have argued that Mullah Omar, in fact, was not referring to the Taliban leader Mullah Mansoor but to the renegade Mullah Mansoor Dadullah. If the dating of the audio is correct, it could very well be that Mullah Omar was talking about Dadullah as he was expelled from the Taliban later that year by Mullah Omar after Dadullah took over a senior military commander position from his older brother Mullah Dadullah Akhund, who was killed in 2007. Whether this is the case or not, it has not prevented Islamic State followers from using the recording to sow doubt about the legitimacy of Mullah Mansoor and, as a result, of al-Zawahiri.
 Ayman al-Zawahiri, “Zawahiri Pledges Allegiance to New Afghan Taliban Leader in Audio Speech,” SITE Intelligence Group, August 13, 2015.
 Vahid Brown, “The facade of allegiance: Bin Laden’s dubious pledge to Mullah Omar,” CTC Sentinel 3:1 (2010).
 See “Cracks in the Foundation: Leadership Schisms in al-Qa`ida 1989-2006,” Combating Terrorism Center at West Point, September 2007; Paul Cruickshank, “Al-Qaeda’s new course examining Ayman al-Zawahiri’s strategic direction,” IHS Defense, Risk and Security Consulting, May 2012.
 Nic Robertson and Jamie Crawford, “Obama: Taliban Leader’s Death Marks a Milestone,” CNN, May 23, 2016.
 Barak Mendelsohn, The al-Qaeda franchise: the expansion of al-Qaeda and its consequences (New York, NY: Oxford University Press, 2016).
 “Al-Zawahiri appointed al Qaeda’s new leader, jihadist websites say,” CNN, June 16, 2011.
 For more information on al-Zawahiri’s strategy, see Cruickshank.
 Andrew Higgins and Alan Cullison, “Saga of Dr. Zawahri Sheds Light On the Roots of al Qaeda Terror,” Wall Street Journal, July 2, 2002.
 Lianne Kennedy Boudali, “The GSPC: Newest Franchise in al-Qa`ida’s Global Jihad,” Combating Terrorism Center at West Point, April 2007.
 Rita Katz, “Zawahiri’s Pledge to the Taliban will Test al-Qaeda’s Cohesion,” SITE Intelligence Group, August 14, 2015.
 Mujib Mashal and Taimoor Shah, “Taliban Chief Rebuked by Religious Leaders in Sign of Turmoil,” New York Times, December 24, 2015.
 Bill Roggio, “Dissident Taliban commander claims Pakistani intel ordered him to conduct assassinations, attacks in Afghanistan,” The Long War Journal, September 7, 2015; Mehsud., Vol. 8 Issue 10, October 2015.
 Taimoor Shah and David Jolly, “Leader of Taliban Splinter Group Allied With ISIS Is Killed,” New York Times, December 1, 2015.
 Abu Mohammed Al-Adnani, “The State of Islam Will Remain Safe” (transcription of the speech), Al Furqan Media, August 7, 2011.
 “Interview with the Wali of Khurasan,” Dabiq, issue 13. In addition, for an interview with former al-Shabaab fighter Abu Muharib as-Sumali, who accuses the Taliban of following ‘Sykes-Picot Politics,’ see ”Interview with: Abu Muharib as-Sumali,” Dabiq, issue 12.
 ”Forewords,” Dabiq, issue 11.
 Thomas Joscelyn, “Al Qaeda renews its oath of allegiance to Taliban leader Mullah Omar,” The Long War Journal, July 21, 2014; Zawahiri’s Mullah Omar Problem, Soufan Group Intel Brief, August 5, 2015.
 “Interview with: The Wali of Khurasan.”
 Personal interview (Hamming), Islamic State members on Twitter and Telegram, January-February 2016.
 “Ali Ahmed: ‘Mullah ‘Umar said about Akhtar Mansur: This man has the potential to become an apostate, and I would never be pleased with him to become the emir,’” YouTube, September 10, 2015. Mullah Umar audio clip is available on YouTube; see also “What is the reality behind Mullah ‘Umar’s warning against having Mullah Akhtar Mansur to succeed him,” Assabeel.net, August 6, 2015.
 Bill Roggio, ”Mullah Omar’s brother and son swear allegiance to new Taliban emir,” The Long War Journal, September 15, 2015.
 See Mehsud.
 Michael Pearson, Masoud Popalzai, and Zahra Ullah, “Death toll rises after Taliban attack in Kabul,” CNN, April 20, 2016.
 Nick Paton Walsh, “Al Qaeda ‘very active’ in Afghanistan: U.S. Commander,” CNN, April 13, 2016.
 James Mackenzie and Paul Tait, ”Al Qaeda re-emerges as challenge for U.S., NATO in Afghanistan,” Reuters, April 15, 2016.
 Bill Roggio and Thomas Joscelyn, “New Taliban emir accepts al Qaeda’s oath of allegiance,” The Long War Journal, August 14, 2015.
 Bill Roggio and Thomas Joscelyn, ”The Taliban’s new leadership is allied with al Qaeda,” The Long War Journal, July 31, 2015.
 “Al-Qaeda Official Hussam Abdul Raouf Echoes Zawahiri’s Pledge to Mullah Akhtar, Mourns Mullah Omar,” SITE Intelligence Group, October 5, 2015.
 Bill Roggio, “Senior Islamic State Khorasan leaders defect to Taliban,” The Long War Journal, April 11, 2016.
 Barbara Sude, “Assessing al-Qa`ida Central’s resilience,” CTC Sentinel 8:9 (2015); Michael Morell, “Fourteen years and Counting: The Evolving Terrorist Threat,” CTC Sentinel 8:9 (2015).
 James Mackenzie and Paul Tait, ”Al Qaeda re-emerges as challenge for U.S., NATO in Afghanistan,” Reuters, April 15, 2016.