The Islamic State Threat in Taliban Afghanistan: Tracing the Resurgence of Islamic State Khorasan

Abstract: Although the Islamic State’s official affiliate in Afghanistan, Islamic State Khorasan (ISK), first emerged as a threat in 2015, its global notoriety was heightened when it struck the Kabul airport during the Taliban takeover of the city in August 2021, leading to questions about the future stability of the country and the Taliban’s ability to contain the revived terrorist threat. The Taliban’s takeover of Kabul, combined with an unconditional U.S. withdrawal and a collapsed Afghan government, generated new opportunities for ISK to reinvigorate its violent campaign following years of significant manpower and territorial losses. Given the absence of multilateral counterterrorism pressure, the Taliban’s limited capacity to govern, and a worsening humanitarian crisis in Afghanistan, ISK now finds itself perhaps in the most permissive environment yet to rebuild, rally, and expand. As the Taliban continue to struggle with their transition to a state actor, ISK enjoys unprecedented opportunities to forge opportunistic ties with local militant groups in need of jihadi alliances and to recruit from communities dissatisfied with the Taliban’s rule. If regional powers do not engage in a coordinated security strategy with the Taliban, they may bear the consequences of the growing ISK-Taliban conflict.

The suicide bombing that struck the Kabul airport in August 2021 not only shocked the world due to the hundreds it left dead or wounded,1 it also refocused attention on the threat of the Islamic State Khorasan Province (often abbreviated to ISIS-K or ISK). The attack ushered in urgent questions about the implications of the ISK threat on the remainder of U.S. withdrawal efforts, the stability of a Taliban-controlled Afghanistan, and the security of the country’s neighbors. While the spectacular nature of the Kabul airport attack led many to view ISK as a renewed threat in the country, warning signs of a resurgent ISK had actually started to permeate in the preceding year. The Taliban’s swift takeover of Afghanistan, along with an abysmal collapse of the Afghan government,2 created new opportunities for ISK to undermine the legitimacy and control of an internationally isolated Taliban. ISK is now present in almost every province of Afghanistan, according to the United Nations,3 as Taliban forces engage in a deadly counterinsurgency campaign against their jihadi rivals with limited measurable success reported thus far.4 Understanding the future trajectory of ISK, its rivalry with the Taliban, and the regional security risks it poses requires tracing the adaptation of the group’s violent strategies in various periods of its existence: the early period of its emergence, years of intense U.S. and Afghan forces-led military operations, and finally, the period of its intensified battle with the Taliban after the U.S. withdrawal.

In 2015, while U.S. and Afghan forces were still battling the Taliban insurgency, Islamic State-Khorasan, the Islamic State’s official affiliate in the Afghanistan region, began to create space for itself by adopting a strategy that focused on coopting opportunistic militant organizations,5 while differentiating itself from the other dominant groups.6 On one hand, cooption of groups such as Lashkar-e-Jhangvi and the Islamic Movement of Uzbekistan provided ISK with expanded expertise and regional geographical knowledge, and curtailed competition for recruits. On the other hand, differentiation from other groups, most prominently the Afghan Taliban—but also groups such as Lashkar-e-Taiba—created opportunities for ISK to persuade militants to switch allegiances for both practical and ideological reasons.

In early 2022, only three years away from marking a decade of formal existence in the region, ISK has shown itself to be a persistent threat to the stability of Afghanistan and its neighbors. In this article, the authors draw on original data on ISK-claimed attacks; propaganda releases by ISK and its competitors (including radio broadcasts); captured internal documents, which reveal communication between Islamic State-Central (ISC) and ISK; and finally, the authors’ discussions with former Afghan government members, Taliban officials, and tribal elders in Nangarhar and Kunar.7 To trace ISK’s pathway to its present state, this article unfolds in four main parts. The first traces the evolution of the group from 2015 to 2019, including the nature of ISC’s engagement with ISK during its earlier years.8 The second focuses on ISK’s resurgence in 2020 and 2021, and highlights its efforts to rebuild its militant base through multiple channels. The third section outlines ISK’s relationship with three groups in the region that are likely to remain its key challengers—Tehrik-e-Taliban Pakistan, al-Qa`ida, and the Afghan Taliban. Finally, the authors conclude the article by highlighting some of the regional security implications associated with a resurgent ISK.

The Evolution of Islamic State Khorasan (2015-2019)
The official announcement of ISK’s formation was made in January 2015 via an audio recording by the Islamic State’s then spokesman Abu Muhammad al-Adnani. However, efforts to set up the affiliate materialized prior to this announcement. Early defections to ISK through public pledges to Abu Bakr al-Baghdadi included nine former members of al-Qa`ida in March 2014,9 as well as six Tehrik-i-Taliban Pakistan (TTP) commanders joining the nascent Islamic State Khorasan in October 2014.10 Hafiz Saeed Khan’s (a former TTP commander) appointment to the top leadership position of the group in 2015 was an early indication that the affiliate was going to draw heavily from the local militant infrastructure.

Since ISK’s emergence in 2015, the group’s operational activity has spanned virtually every province in Afghanistan and Pakistan. At various points, this included the consolidation and governing of territory in parts of northern and northeast Afghanistan, especially in Nangarhar province. Elsewhere in Afghanistan in 2015, fledgling ISK nodes, mostly the product of breakaway Taliban or Taliban-aligned groups, were contained by the Taliban and/or U.S. airstrikes and Afghan ground force interventions.11 But it was in Nangarhar’s southern districts that ISK enjoyed numerous advantages to support its initial territorial project.12 Reporting on the group’s early expansion efforts indicated that ISK, at its height, controlled eight districts across southern Nangarhar,13 amassing operational resources and personnel around its de facto headquarters in the valleys of Achin district. It was not until 2016 that a number of convening factors initiated the gradual decline in ISK’s territorial control: The Taliban mobilized ground forces to limit ISK’s expansion in and around Nangarhar;14 the Obama White House granted expanded ISK targeting authorization authorities to the Pentagon;15 a U.S. and Afghan-allied coalition ground offensive backed by U.S. airpower killed or captured hundreds of ISK rank-and-file and leadership;16 and additional Afghan units arrived to help clear and hold territory regained from ISK control.17

From 2015 to 2019, state-led operations captured, killed, or forced the surrender of over 10,000 of the group’s affiliated members in Afghanistan and Pakistan combined, including hundreds of upper- and lower-level leadership.18 As the end of the decade approached, ISK’s territorial holdings in Nangarhar were depleted, and the group’s remaining forces had either surrendered en masse to the previous government or relocated north to neighboring Kunar province or into major urban areas.19

Over the same period from 2015 to 2019, ISK’s attack operations followed a trajectory of rise and decline. As Figure 1 shows,a the total number of ISK’s attacks (in Afghanistan and Pakistan combined) rose each year from 2015 to 2017 before falling from 2017 to 2019, and as Figure 2 shows, its average casualty count (the number it killed and wounded per attack) rose from 2015 to 2018 before declining in 2019. ISK conducted attacks in over 25 provinces across Afghanistan and Pakistan from 2015 to 2019, inflicting almost 6,800 casualties (killed and wounded) in the former and 2,073 casualties in the latter. By far, the hardest hit city during this period was Kabul (nearly 3,900 casualties), followed by Jalalabad (over 1,000 casualties) in Afghanistan and Quetta in Pakistan (over 750 casualties). In both countries, the majority of ISK’s attacks have targeted the state, including infrastructure and/or security and government personnel, but especially police forces.20 Prior to 2020, various soft targets, such as religious institutions and public spaces, had also consistently been targeted, with Afghanistan’s Shi`a and Pakistan’s Sufi communities frequently attacked, including with suicide attacks.21

Figure 2: Average Casualty Count Per ISK Attack (2015-2021)

The ISK Relationship with Islamic State Central
Despite periods of intense targeting pressure, however, internal ISK documents22 reveal an organization very much dedicated to the method of Islamic State Central (ISC) in Iraq and Syria. The documents also shed light on ISK’s initial goals. For example, the authors reviewed a memo dated July 2016 from ISK that appeared to be penned after the death of ISK’s first emir,23 Hafiz Saeed Khan. The memo presented a status update from ISK, appearing to be intended for ISC. The letter states:

We appointed an Emir of War for the Khurasan province, and we formed a military shura for the province as well … The brothers of the Khurasan province were relieved by the establishment of a Sharia committee for disputed issues, and for that reason, application of the Islamic State’s methodology has been much easier.

Even in the face of reported significant manpower and leadership losses in the first half of 2016, ISK appeared to have prioritized multiple lines of organizational development and administrative expansions. Various reports about ISK’s losses provide details about the wide-ranging activities of its members; these reports indicate that targeted ISK members were performing duties across several administrative bodies with comparative structures in ISC’s bureaucratic protostate.24 These included military training, battlefield operations, and martyrdom operations; judicial and religious matters; media, proselytization, and recruitment; and logistics, information technologies, and financial bodies.25

While there is much uncertainty surrounding the links between ISC and ISK, open-source reports as well as captured materials from Afghanistan indicate that ISC played an important role in facilitating the establishment of ISK, at least in its early years. Ranging from facilitation of meetings to provision of general guidance on governance, as well as dispute resolution, ISC helped ISK build its roots in the region.

To understand the level of engagement between ISK and ISC in its early years, the authors reviewed a sample of captured materials from Afghanistan (in Dari, Pashto, and Urdu) to highlight the nature of guidance provided to ISK as well as the types of communication between the two entities. From the set of documents that appear to be intended to provide the Islamic State’s provinces with advice,b one document stamped with an “Al-Hisbah” logo, which refers to the Islamic State’s religious enforcement police, outlines a request to all emirs to report Al-Hisbah activities conducted between October 2014 and January 2015, and then on a monthly basis thereafter. The memo requests information regarding the settlement of issues, cases forwarded to courts, propaganda distributed to the public, lectures delivered, material possessions confiscated, and disciplinary measures taken. Other documents with the Islamic State’s Al-Hisbah logo outline general rules on various other topics, including the sharing and publishing of photos of female ‘sex slaves’ on social media, use of satellite receivers, and dealing with ‘inappropriate’ books, audio, and video. While these documents appear to be generic guidance by ISC for its ‘provinces’ around the world rather than for ISK specifically, their existence indicates that ISC generally had an interest in shaping ISK’s behavior on the ground.26

ISK also appears to have had strict requirements on the frequency of communication with ISC, especially in reporting their military operations and achievements. A collection of documents suggest that ISC was regularly requesting military reports, and evidence of ISK’s achievements. Details within the documents reveal that ISK was reporting figures on membership, factions that had pledged allegiance, appointment of leaders, outcomes of clashes with the Taliban, and operations in Pakistan. While these documents are not explicitly addressed to anyone by name, they appear to be updates intended for ISC. In addition to general guidance documents, and ISK’s status updates, the documents also indicate that ISK was relaying their problems to ISC during times of difficulty, especially when the group suffered losses or needed money. Related documents suggest that ISC was indeed transferring funds to ISK, at least during its earlier years.

Collectively, the sample of documents reviewed sheds light on how ISC was involved in various ways in the set-up of ISK in its early years, possibly channeling funds and also monitoring ISK’s strategy and tactics to some extent. While today these links between ISC and ISK remain unclear, more recently, ISK has been regularly featured as a high-performing province in ISC’s propaganda and received direct praise for some of its high-profile attacks, such as its prison siege in Jalalabad City in 2020 and the attack on Kabul airport in August 2021.27

By the end of 2019, declines in territory, manpower, and overall capacity left ISK significantly weakened and forced it to focus operations predominantly in urban centers.28 Although the group’s broader operational activity was markedly declined in 2019 from previous years, its continued dedication to intermittently launch attacks signaled the potential for a resurgence in 2020, especially in the absence of multilateral counterterrorism efforts.

A Resurgent ISK (2020-2021)
This section focuses on ISK’s resurgence starting in 2020 and carrying into 2021. Leveraging an original database that captures ISK-claimed attacks, as well as the group’s own propaganda, this section traces changes in ISK’s operational behavior, the role of its new leader in its revival, and finally the group’s attempts to rebuild its militant base.

Revamping Operations
Warning signs of ISK’s resurgence began to surface around mid-2020, while the United States continued to engage in peace talks with the Taliban. Starting in June 2020, ISK attacks in Afghanistan steadily rose month after month all the way through to June 2021, surging from just three attacks in June 2020 to 41 attacks in June 2021.29 Highly lethal, sectarian attacks against vulnerable minorities such as Afghanistan’s Hazara communities continued throughout, including a horrific attack against a Hazara girls’ school in Kabul in May 2021 that killed or wounded well over 200 girls and teachers.30 After the devastating August 2021 attack at the Kabul airport killed or wounded hundreds of Afghan civilians—in addition to 13 U.S. service members31—ISK showed no signs of halting its campaign of violence. Attacks targeting houses of worship in Kunduz and Kandahar in October 2021 left hundreds more dead or wounded,32 and additional attacks have since hit Kabul.33

Overall, however, ISK’s average casualty per attack is dramatically lower than in previous years. As Figure 2 shows, in 2021 the group averaged around 5.5 casualties per attack; however, the lower number is the result of a massive surge in the volume of attacks perpetrated by ISK in the year 2021. Including clashes initiated against the Taliban in years past, ISK’s total number of attacks in 2021 is more than double that of the next highest year on record since its formation in 2015, surpassing 340 attacks by the end of December.c The nature of ISK’s attack strategy has shifted, too. In addition to more complex attacks such as the Jalalabad prison break operation in 2020,34 ISK also began attacking infrastructure targets in the spring and summer of 2021, claiming responsibility for three-dozen attacks on electricity pylons and oil tankers,35 advancing a strategy of “economic warfare” designed to challenge the former government and the Taliban’s legitimacy as a state actor.36

During the period of peace negotiations and intra-Afghan talks, ISK’s attacks served to create general chaos and confusion among various political entities, intended to stall political progress. However, in the post-Taliban takeover era, ISK shifted its focus squarely on undermining the Taliban’s legitimacy. Without any external counterterrorism efforts against ISK and given the Taliban’s limited resources and its tenuous control in some parts of the country, ISK has never been better positioned to challenge the Taliban and exploit vulnerable communities. As such, the most significant shift in ISK’s attack strategy over the past year has been its concerted effort to destabilize the Taliban’s weak control over ISK’s former strongholds in Nangarhar province. Since around mid-September 2021, ISK claimed responsibility for 127 attacks in Afghanistan, nearly 100 of which (79 percent) targeted the Taliban alone. Just under 60 percent of ISK’s attacks on the Taliban occurred in Nangarhar (see Figure 3).37 The group has targeted Taliban checkpoints, security convoys, and personnel, but they have also carried out targeted assassinations against members of the former government, media personnel, civil society activists, community elders, and prominent voices in local salafi communities that have spoken out against ISK.38 ISK’s efforts to destabilize the Taliban’s control have forced the latter to expose its hand at counterinsurgency, which has included crackdowns and reprisals against local civilian populations deemed to be supportive of ISK. To date, even declared efforts at mediation with local communities,39 as well as the mobilization of over 1,000 additional Taliban security personnel to assist in securing Nangarhar province,40 have done little to conceal the Taliban’s heavy-handed approach to counterinsurgency,41 one that continues to alienate locals and will likely see the ISK-Taliban conflict persist for the foreseeable future.

Figure 3: ISK Attacks in Afghanistan and Khyber Pakhtunkhwa (Pakistan) (September 18-December 31, 2021)

Rallying Under New Leadership
ISK credits its current governor or top leader, Shahab al-Muhajir, for the group’s resurgence.42 Al-Muhajir, whose real name is Sanaullah Ghafari, hails from the district of Shakardara just north of Kabul and holds an engineering degree from Kabul University.43 He adhered to the salafi ideology in Kabul University under the influence of faculty member and Afghan salafi scholar Abu Obaidullah Mutawakil.44 Al-Muhajir’sd family belonged to a major Afghan jihadi party—Hizbi Islami Gulbadin Hekmatyar (HIG)e—that formed during the pre-Taliban era and participated in fighting the U.S.-allied forces in Afghanistan.45 Al-Muhajir joined the jihadi war in Afghanistan through the same party platform, later joining Taliban factions affiliated with the Haqqani network.46 He had close links to the Haqqani network’s senior commanders, Taj Mir Jawad and Qari Baryal, who ran terrorist networks in the capital. When ISK emerged in Afghanistan, al-Muhajir switched loyalties and eventually rose to the position of deputy head of ISK’s Kabul network.47 Upon his appointment as the new ISK governor in 2020, al-Muhajir was touted as an urban warfare expert, who would avenge “group martyrs” by targeting the Afghan government in urban areas and also pursue the release of ISK imprisoned members.48 According to two senior security officials of the former Afghan government,49 al-Muhajir had an extensive social network in Kabul city that helped his recruitment pipeline. This included young individuals from influential political and warlord families who facilitated ISK activities, at times unknowingly.50 Such personal networks helped al-Muhajir logistically, such as acquiring special security cards and weaponry licenses from senior Afghan government officials, including one issued by the office of the former Afghan vice president Abdul Rashid Dostum.51

ISK’s propaganda generally praises al-Muhajir for three major contributions to the organization.52 First, he is credited with reinvigorating ISK when it was struggling to survive post-2019 after major territorial, leadership, and rank-and-file losses. Secondly, the August 2020 Jalalabad prison break and ISK’s new economic warfare strategy, alluded to above, are attributed to al-Muhajir’s leadership skills.f Finally, al-Muhajir is credited with the high-profile attack in August 2021 on the Kabul airport, which was conducted by Abdul Rahman al-Logari, a member of ISK’s Kabul cell, who had been released from a high-security prison after the Taliban seized control in August 2021.53

Reuniting, Reinforcing, and Diversifying the Ranks
One of al-Muhajir’s major challenges at the helm of an organization faced with territorial and manpower losses was reuniting ISK’s dispersed members and reinforcing and diversifying the group’s ranks to help kick-start its new strategy of urban warfare. To do so, he led ISK on a three-pronged strategy: planned prison breaks, providing amnesty to the more than 1,400 members who surrendered to the previous government,54 and advertising a diverse militant base to cast a wide recruitment net.

In his first public communication to ISK members in early July 2020,55 al-Muhajir called on dispersed members to participate in ISK’s new strategy: guerrilla warfare and urban terrorism. Group members languishing in prisons were also promised rescue. A month later, ISK conducted a highly sophisticated attack on Nangarhar central prisons in Jalalabad city, resulting in the release of over 1,000 prisoners, including 280 ISK inmates. This coordinated assault—the first of its kind for ISK—greatly bolstered al-Muhajir’s burgeoning reputation, as noted above.56

Similarly, other prison breaks that followed soon after the collapse of the former Afghan government allowed hundreds of freed prisoners to rejoin ISK’s ranks. According to various estimates,57 around 2,000-3,000 ISK inmates escaped during and after the fall of the former government, which included senior leaders, commanders, and media propagandists. For example, al-Muhajir’s predecessor, Aslam Farooqi, influential senior ideologue Abu Yazid Abdul Qahir Khurasani,58 g and the Islamic State Jammu and Kashmir branch founder, Aijaz Ahmad Ahangar,59 h were among those freed. A critical aspect of these prison breaks was the release of foreign fighters. The former Afghan government held 400-plus ISK members from 14 countries who escaped during the jailbreaks a day prior to the Taliban’s takeover.60 i Given that these fighters would have been unlikely to return to their home countries (where they would likely be prosecuted), their release from prison has likely provided a boost to ISK’s cadres.

To attract those who had previously surrendered to the government, ISK also announced an amnesty policy that may have lured hundreds of militants back into the ISK fold.61 The issue of the 1,400-plus ISK members who surrendered to the previous government in Kunar in early 2020 was discussed in ISK’s radio broadcasts; according to ISK’s religious edict, some ISK commanders betrayed their fighters, and compelled them to surrender.62 ISK encouraged such fighters to appear before ISK courts and renew their pledges of loyalty to the group.63

Before discussing the third prong of the strategy, it is worth discussing potential sources of recruits for ISK. One source of potential recruits for ISK has been Afghan salafi communitiesj in and around Kabul and Nangarhar, where ISK has attempted to exploit the lack of trust between the Taliban and salafi communities.64 Tensions between the salafi communities and the Taliban were heightened when the aforementioned senior salafi scholar, Abu Obaidullah Mutawakil, was mysteriously abducted and killed in the Afghan capital shortly after the Taliban’s ascent to power.65 Mutawakil had been imprisoned for about two years for alleged links with ISK, but had escaped in the prison breaks during the Taliban takeover in August 2021. After ISK claimed attacks in the wake of Mutawakil’s killing, the Taliban reacted by imposing harsh security measures in salafi communities, closing down mosques, conducting night raids, and abducting and publicly executing dozens of salafi youths.66 Such actions have exacerbated fears among the salafi community of persecution by the Taliban. And ISK has sought to exploit anti-Taliban salafi sentiments, and mobilize individuals against the Taliban.67 By emphasizing that the Taliban are targeting salafis, and often exaggerating or falsely making such claims, ISK has positioned itself to serve as the protector of the salafi community.

Another segment of population for whom joining ISK may appear to be the only feasible way to survive are former Afghan security force members at risk of being persecuted by the Taliban; although reported numbers remain small, developments in late 2021 indicated that some former Afghan forces members had joined ISK in order to resist the Taliban, bringing with them useful intelligence-gathering and fighting techniques.68 As long as the Taliban fail to devise an effective mechanism to reconcile with former Afghan forces, the pool of thousands of former Afghan security officers, fearful and without any future prospects, represents an untapped opportunity for ISK to rebuild itself stronger than ever before.

The third-prong of al-Mujahir’s strategy to potentially attract more recruits, ISK appears to be intentionally advertising the diverse nature of its membership over the last two years. For example, the attack on a Sikh gurudwara in Kabul in March 2020,69 as well as the August 2020 Jalalabad prison break, both involved Indian nationals as perpetrators, according to ISK.70 The perpetrator of the Kunduz attack in October 2021 was claimed by ISK to be a Uighur Muslim.71 By showcasing these attacks as being led by militants of varying backgrounds, ISK may be attempting to appeal to an eclectic pool of militants, which includes Central Asians, Indians, Chinese, as well as Kashmir-based militants.72 The potential for foreign fighters to join the ranks of ISK is worrisome as research indicates that foreign fighters can increase a group’s longevity, its use of suicide operations, and its geographic reach.73 Taken together, ISK appears to be actively boosting its ranks to continue its fight against the Taliban and state actors through a multi-pronged recruitment strategy of prison breaks, amnesty drives, posing as the protector of the salafi community, and recruiting regional militants.

ISK’s Relationship with its Local Competitors
ISK’s relationships, to include both alliances and rivalries, have been key in its emergence and survival. While much research has examined how ISK’s alliances facilitated its upward trajectory,74 this section focuses on ISK’s competitors in the region, which serve as its direct or indirect challengers: the Tehrik-i-Taliban Pakistan (TTP), al-Qaida and its South Asian affiliate (al-Qaida in the Indian Subcontinent, or AQIS), and the Afghan Taliban.k Understanding ISK’s relationships with these three organizations can provide insights into ISK’s current and future behavior.

Tehrik-i-Taliban Pakistan
Upon its formation, ISK labeled all other Islamist groups religiously illegitimate and declared itself to be the sole legitimate leader of the global ummah and caliphate movement.75 One of ISK’s main target audiences has been the TTP, given TTP’s anti-Pakistan agenda and ISK founding leadership’s strong ties with various TTP groups.76 ISK formed at a time when TTP was splintered and suffering from several internal disputes; this resulted in the defection of TTP members to ISK, including the entire TTP Orakzai chapter and part of its Bajaur chapter (according to the TTP itself).77 ISK founding governor and former TTP commander, Hafiz Saeed Khan, was optimistic of TTP being subsumed by ISK, as evident from a letter from Khan to ISC, dated June 22, 2016, that the TTP would not be able to survive the rise of ISK.78 In his words:

As for the TTP, headed by Mulla Fadlallah [Fadlullah], it is on the verge of collapsing because of the conflicts that have taken place within it. Praise to Allah. We know that it had tried to smooth out some conflicts inside the governorate, but the state of its personnel became such that they are accusing one another of being spies and agents. This is a victory Allah granted the soldiers of the Caliphate.

While ISK’s strong anti-Pakistan narrative appealed to TTP fighters, its brutal war with the Afghan Taliban became an obstacle for TTP to cooperate with ISK, given TTP’s loyalty to the Afghan Taliban. To stem the flow of member defections to ISK, the TTP published a detailed religious edict in 2015 criticizing and nullifying the Islamic State’s caliphate.79 Interestingly, although the TTP maintained bases in ISK’s strongholds in Kunar and Nangarhar, reports about ISK-TTP clashes have been largely nonexistent. ISK’s decline in 2019, however, was paralleled by TTP’s own resurgence,80 and for the first time, in July 2020, the TTP declared ISK to be a tool of the Pakistani establishment, set out to destroy jihadi movements.81 Overall, given the Afghan Taliban’s ascendancy to power and the TTP’s reinvigorated operations and celebration of the former’s victory, it is possible that the relationship between the TTP and ISK becomes more hostile in the future.

As ISK intensified its battle with the Afghan Taliban in 2020 and the TTP publicly renewed its pledge of allegiance to the Afghan Taliban,82 ISK turned to disparaging the TTP as well. In August 2021, ISK published a book authored by ideologue Abu Saad Muhammad al-Khurasani in which he declared the TTP leadership to be apostates.83 Within the publication, he accused the TTP of being a puppet of the former Afghan government and seeking external support from Indian intelligence agencies.84 The book discussed the potential of the TTP striking a deal with the Pakistani state for their own worldly interests, and encouraged TTP fighters to join ISK’s “true” jihad. A similar publication was released by the Islamic State’s Pakistani chapter in December 2021,85 which urged TTP fighters to revolt against their leadership in light of the group’s recent but no longer ongoing negotiations with the Pakistani state. These changing dynamics between ISK and the TTP suggest rising tensions between the two groups in the future, as ISK seems intent on luring TTP members to its own fold for its long war against Afghan Taliban rule.

The Afghan Taliban, however, have been proactive in their efforts to prevent ISK or any other rival group from exploiting fractures within the regional jihadi landscape. For example, according to sources within Afghanistan, the Afghan Taliban held a secret meeting of all allied jihadis near Kandahar to discuss ISK shortly before its February 2020 Doha deal with the United States.86 The Afghan Taliban asked all gathered militants to join one of the Afghan Taliban’s vetted groups if they wanted to remain in Afghanistan. Later that year, a series of mergers saw 10 anti-state Pakistani militant groups, including all TTP splinters, rejoining the TTP to merge into a single entity.87 What remains unclear, however, is the extent to which such efforts will garner success in the long-term in containing ISK’s recruitment drive.

Al-Qaida The formation of an Islamic State province in the Afghanistan-Pakistan region extended the Islamic State-al-Qaida rivalry into South and Central Asia. Yet that rivalry is a nuanced one given the presence of the Taliban and its status as ISK’s primary local adversary. One of ISK’s justifications for its war with the Taliban is the latter’s professed attempts to distance themselves from al-Qaida and terrorist groups in general.88 An examination of ISK’s published propaganda shows criticism largely directed toward al-Qaida’s current emir, Ayman al-Zawahiri, who is labeled an apostate for his obedience to the Afghan Taliban.89 At the same time, in a fashion similar to ISC, ISK propaganda frequently praises al-Qaida’s previous head and founder, Usama bin Ladin, and paints the Islamic State as the rightful inheritor of bin Ladin’s jihadi legacy and al-Zawahiri as an errant and illegitimate successor.90 Like ISC, the focus of ISK’s propaganda on al-Zawahiri in particular could partially be the result of the influence of Afghanistan-Pakistan region-based Arab leaders of al-Qaida who pledged allegiance to ISK, in addition to the fact that al-Zawahiri is the leader of ISC’s main rival group that has been in an open conflict with ISC since its early years. Several of the initial al-Qaida defectors to ISK swapped alliances due to differences over ideological and organizational matters with al-Zawahiri and his son-in-law, Abu Dujjana al-Basha, who held an influential position in the al-Qaida central leadership.l

Intense counterterrorism pressure against al-Qaida in Afghanistan and Pakistan since 9/11 resulted in the death of bin Ladin91 and the appointment of al-Zawahiri as al-Qaida’s leader. Subsequently, senior al-Qaida defectors to the Islamic State encouraged hundreds of local Afghan and Pakistani cadres to also join ISK to continue their global jihad.92 According to former Afghan government senior security officials,93 m a large number of ISK’s founding cadres were former al-Qaida members, which provided ISK with highly skilled trainers and experts.94 n

AQIS’ founding leaders, Ahmad Farooq and Usama Mahmood,95 have attributed the loss of al-Qaida members to ISK to the Islamic State’s flashy, ‘Hollywood-style’ propaganda and territorial captures in Iraq and Syria, among other factors.96 Against the backdrop of al-Qaida members joining ISK, al-Zawahiri announced the establishment of AQIS around September 2014.o While some view the formation of AQIS as a reaction to the Islamic State’s announcement of a caliphate, especially due to defections of al-Qaida members in early 2014, in its first edition of its Resurgence magazine, al-Qaida relayed the message that the “establishment of this organization is a direct result of the merger of several groups that have been engaged in Jihad in this region for several years.”97 In another edition of the magazine released the following year (mid-2015), a well-known al-Qaida member—Adam Yahiye Gadahn—directly refuted accusations that AQIS had been created to counter the growing influence of the Islamic State. Per Gadahn, plans for AQIS were long in the making and finalized in mid-2013, and as such, “the founding of the new branch [AQIS] had absolutely nothing to do with any perceived or presumed rivalry between al-Qaida and Islamic State.”98 p

With the U.S. operation that resulted in the death of al-Baghdadi and ISK’s territorial collapse in 2019, AQIS announced an amnesty for al-Qaida cadres who joined ISK,99 although it remains unclear how many reverted back. Looking forward, AQIS and ISK are likely to continue their rivalry in South and Central Asia, which may intensify as the two compete for recruits and their parent organizations (ISC and al-Qaida) compete to be the legitimate leaders of global jihad. On one hand, given al-Qaida and AQIS’ limited observable reach and activity in the current environment, ISK may continue to dominate the regional militant landscape as the ascendent transnational jihadi brand. On the other hand, given al-Qaida’s close historical relationship with the Taliban, the latter’s takeover in Afghanistan may allow AQIS greater opportunities to increase its own influence. How the rivalry between the two groups plays out will ultimately be influenced by the Taliban’s ability to constrain ISK and reinforce their control within Afghanistan.

The Afghan Taliban
Since its inception, ISK has viewed the Afghan Taliban as its main strategic rival in the region.100 In a quest to outbid and outcompete its rival, ISK has not only attacked Afghan Taliban targets regularly since 2015, but also recruited heavily from the organization’s ranks and leadership, which ISK has categorized into three general groups: first, the ‘sincere Taliban jihadis’ who defected to join ISK; second, those who kept a neutral stance toward ISK; and third, the ones who are the puppets of regional governments and motivated by personal interests.101 ISK has made delegitimizing the Afghan Taliban’s purity as a jihadi movement one of its main messaging priorities. This is reflected in ISK’s media campaigns for the last several years, which consistently highlight idolatrous Afghan Taliban-supported or tacitly approved religious and cultural practices, as well as relationships with foreign states that ISK views as heretical. Undermining the Afghan Taliban’s legitimacy as a jihadi movement is a key pillar to ISK’s organizational identity that is unlikely to change.102 Since the former took power, ISK’s strategy has evolved not only to challenge the Afghan Taliban’s legitimacy as the predominant jihadi force in the region (given their negotiations with the United States, and links to Pakistan, China, and Iran), but also their competency as a governing actor.103

ISK’s two-pronged attack on the Afghan Taliban’s legitimacy104 is likely to persist as long as the Taliban remain in power. Early assessments of the Taliban’s governance efforts suggest ISK’s strategy is paying dividends, as the Taliban remain more preoccupied with maintaining the organization’s internal cohesion, reverting to their “default wartime style and operational mode,” and relying on harsh restrictions, extrajudicial raids, and violence to establish some semblance of control.105 Such oppressive tactics, and a failure to provide human security, are likely to increase discontent with the Taliban’s rule, which can play into ISK’s hands, given the latter’s anti-Taliban stance.

Initially, the Taliban leadership approached ISC leadership in Syria, requesting that al-Baghdadi avoid establishing a parallel jihadi network in Afghanistan, which was openly rejected by the Islamic State’s spokesman at the time, Abu Muhammad al-Adnani.106 By the time of the Afghan government’s fall in 2021, ISK and the Afghan Taliban had clashed in at least 16 provinces across Afghanistan.107 Both organizations inflicted hundreds of casualties upon the other, leaving tens of thousands of civilians either killed or displaced as a result of their fighting.108 After 2015, the majority of the ISK-Taliban rivalry became concentrated in or around ISK’s territorial holdings in Nangarhar and Kunar in the northeast, and Jowzjan in the north.109 The Taliban organized multiple mobilizations of fighters to counter ISK around these main pockets of ISK territorial control, which coincided with U.S. and Afghan airstrikes and ground offensives, including significant targeting of ISK leadership.110

Within the ISK-Taliban rivalry, ISK’s strategy to poach Taliban members and gain recruits in Afghanistan has centered on exploiting the Taliban’s tense relationship with salafis, a factor often overlooked.111 Tensions between ISK and the Taliban intensified after the salafis rose to key leadership positions within ISK in the wake of the killing of ISK’s founding governor.112 Abdul Haseeb Logari, ISK’s second governor, was a salafi scholar, and Sheikh Jalaluddin, an influential salafi scholar in the Pashtun belt of Afghanistan and Pakistan, became the group’s chief ideologue.q This framed ISK’s battle with the Taliban more than before as a fight between the salafis’ version of the sharia and that of the “ideologically corrupt Hanfists Muslims.”113 r As Logari implemented a salafi-interpreted, sharia-based system in ISK-controlled territories in Afghanistan, a large number of Afghan salafis joined ISK’s ranks.114 As such, whether opportunistically or by design, ISK became an armed platform for salafi supremacy, which has now developed into a core vector of ISK’s insurgency efforts in northeastern Afghanistan as outlined above.115

Since the Taliban’s takeover of Afghanistan in 2021, ISK has remained relentlessly committed to targeting the Afghan Taliban, highlighting the latter’s inability to protect civilians at home or contain terrorism. Unlike during their previous years of rule, the Taliban are faced with tackling an enemy that has poached the Taliban’s own members as well as those of their allies, and that follows an even more radical interpretation of Islam for justifying its violence. Although many argue that ISK’s salafi ideology has a limited audience in Afghanistan, the Taliban do have a long list of enemies in Afghanistan, and some of them may be willing to cooperate with ISK to counter the Taliban’s influence, due to lack of other organized resistance efforts. While this is not a given, as opponents of the Taliban may seek out alternative courses of action, Afghan political history provides several instances of such pragmatism guiding cooperation and alliances, such as in the case of Gulbadin Hekmatyar, emir of Hizb-i-Islami (HIG). In a public statement issued in 2015, Hekmatyar urged his fighters to support ISK in the Taliban-ISK war, arguing that ISK had never transgressed against the HIG while the Taliban had oppressed HIG members on several occasions.116 s Similarly, at a public gathering hosted in September 2021 in Paris by exiled Northern Resistance Front Afghan supporters, a speaker suggested to party members that ISK may be the best mechanism to counter the Taliban.117

As noted above, the Taliban continue to be engaged in a counterinsurgency campaign against ISK, particularly in ISK’s former stronghold of Nangarhar. ISK’s attacks against Taliban checkpoints, security convoys, and personnel, designed to destabilize Taliban control, have exposed the weaknesses in the latter’s counterinsurgency approach, which Colin Clarke and Jonathan Schroden recently labeled “brutally ineffective.”118 As they rightly point out, night raids,119 extrajudicial killings of suspected ISK members,120 and indiscriminate crackdowns on locals,121 among other tactics, contribute to a broader strategy of counterinsurgency via brute force that empirically has been shown to be ill-suited to defeat insurgent groups.122 The combination of ISK’s history of resilience against immense targeting pressure (including airstrikes and ground operations),123 its ability to create pockets of territorial control in Afghanistan,124 and the Taliban’s oppressive counterinsurgency strategy bodes poorly for the security situation going forward. And a resurgent ISK not only challenges the Taliban’s legitimacy, it also depletes the group’s limited resources as the latter struggles to grapple with the growing humanitarian catastrophe at home.125 As Clarke and Schroden also contend, the resurgence of ISK also has the potential to multiply the number of armed resistance groups in Afghanistan, who may conclude that armed resistance is not only viable, but also necessary.126

In sum, ISK and the Taliban’s rivalry is likely to intensify into the future given the divergence in their goals and ideologies, and competition for influence. For ISK, targeting the Taliban serves multiple goals, but perhaps most importantly, it allows ISK to simultaneously demonstrate its own resolve and operational capacity while undermining the Taliban’s reputation—allowing it to position itself as the dominant militant player in the region and the partner of choice for local groups seeking allies.

Regional Security Implications of a Resurgent ISK
With the Afghan Taliban now in power, the question that has come to be highly debated is whether they are capable of constraining ISK. But two associated issues are perhaps equally critical to consider; the first is the cost associated with the Taliban diverting resources to tackle a resurgent ISK rather than establishing basic governance, and the second is the implications for the broader region if the Taliban and ISK remain engaged in a prolonged battle that could potentially last for several years.

The debilitating human costs of a prolonged battle between ISK and the Taliban have been felt through the thousands of civilian casualties and tens of thousands more displaced over the past seven years.127 Additionally, the recent wave of attacks conducted by ISK, including the Kabul airport attack and attacks against the region’s Shi`a communities, have highlighted the severe implications of ISK’s resurgence and continued survival on the Taliban’s ability to govern as a state actor. But ISK is not just the Taliban’s problem. The group’s strategy of delegitimizing the Taliban, merging its transnational agenda with experienced regionally oriented groups, and building a diverse militant base of members with over a dozen nationalities and terrorist group affiliations creates a threat for all of Afghanistan’s neighbors.128

One of the main manifestations of that threat is ISK’s ability to align its own agenda with the interests of numerous regionally oriented groups—something that nationalistic groups like the Afghan Taliban are growing increasingly ill-equipped to offer. Given the Taliban’s desire to be recognized as a legitimate entity by the international community and their professed inclination to distance themselves from terrorist groups, coupled with al-Qa`ida’s relatively weakened status, ISK has positioned itself as the most viable option for anti-state groups such as the Islamic Movement of Uzbekistan129 and East Turkistan Islamic Movement/Turkistan Islamic Party,130 which have suffered losses from counterterrorism operations and may be seeking to join an ascendant jihadi group that also meets their fundamental goals. Whether local groups’ primary motivations are to target the governments of Pakistan, India, China, Central Asian countries, and/or Muslim and non-Muslim minority populations, ISK has something to offer all of them.

ISK’s initial upward trajectory of violence was derived in part from operational cooperation with other groups such as Lashkar-e-Jhangvi (LeJ) and suspected links with Jamaat-ul-Ahrar (JuA) operatives.131 LeJ, for example, has played a critical role in facilitating recruitment for ISK, specifically from the Brahui ethnic community in Pakistan’s Baluchistan province.132 But ISK’s emergence in the region also appeared to influence LeJ and JuA’s own operations within Pakistan; after suspected links with ISK emerged, both groups expanded their areas of operations beyond their traditional strongholds, and their targeting priorities seemed to align with ISK’s priorities.133 JuA’s return to the Pakistani Taliban’s fold highlights another risk that exists across the region: militants switching allegiances and/or having inter-group relations makes membership fluid and difficult to distinguish between groups.134 Such problems are likely to be compounded as militants relocate to Afghanistan and affiliate themselves with the Islamic State,135 but also maintain their self-serving agendas.

ISK’s sources of strength are drawn from across the region, and its survival is likely to exacerbate violence across the region and disrupt any plans for Afghanistan’s stability rooted in geo-economics.136 It also opens up the country for renewed proxy warfare.137 Given that the Taliban have so far been incapable of delivering proper security to Afghan citizens and have yet to receive necessary levels of foreign assistance to stem the growing humanitarian crisis, the Taliban’s control and power may erode quickly.

In short, ISK’s survival poses significant risks, which regional players will be ill-advised to tolerate. Instead of watching the Taliban continue to clash with ISK, countries looking to counter ISK may need to proactively develop a joint security mechanism that addresses ISK’s key sources of strength and ultimately help the Taliban constrain the group within Afghanistan. For example, identifying and sharing intelligence regarding inter-group activity related to ISK and its cross-border alliances could help dismantle ISK’s operational alliances, which are an important source of the group’s strength. Another area of coordination could be dismantling supply chains of smuggling and inter-group linkages within each country’s shadow economy, which facilitate ISK financing. Finally, sharing intelligence on the profiles of captured ISK militants, including their prior affiliations, could help identify channels of ISK recruitment. Such cooperation could go far to ensure that any kinetic counterterrorism measures against ISK contribute to undermining the group rather than simply resulting in its decentralization and dispersion across the region.