**4. Conclusions**

The meteoric rise of ISIS, in 2014, has taken the world by surprise. After being nearly decimated in the end of 2000s, the former al-Qaeda affiliate managed to break through the Iraqi borders and at its height control territory of a significant size. The article demonstrated that the ripples of IS's rise were felt across the international system and the jihadi subsystem. The declaration of the 'Caliphate' and al-Baghdadi's claim to the role of Caliph raised important questions regarding IS's interaction with the international order and the jihadi movement. The answers to these questions help us understand the true nature of IS's challenge and that of other groups that might try to emulate IS's paradigm in the future.

The article showed that, from mid-2014 until 2016, IS was by all accounts a de facto state, which though did not perceive itself as territorially bounded. Contrary to past examples of revolutionary states, it had no intention to fully 'socialize' in the system's norms and logic because it negated the premises of the Westphalian system, which contravenes the notion of a united ummah. Therefore, it does not see itself as part of and does not have any commitments towards the international community. All states but the 'Islamic State' are considered illegitimate and IS can o ffer them nothing more than a *temporary truce*. In this regard, by demanding the recognition of its supreme authority as a Caliphate, IS cannot succumb to the structural pressures to become a 'normal' state, without compromising its global brand. IS's extremism informed the discussion around possible strategies to counter its territorial growth and appeal. Although there were some proponents of a containment strategy, which rested on the idea that it is better to allow IS to fail rather than forcibly dismantle it, the international coalition opted for an active destruction strategy, assuming that containment would require time that, in light of IS's terrorist attacks and increasing refugee flows, was not available.

Concerns around its global brand do not only a ffect IS's authority and interaction with the international—Westphalian—system, but also the jihadi (sub)system. IS operates in a competitive jihadi market, which forces groups to preserve their ideological edge to keep competition in check and attract more fighters and resources than their competitors. By the same token, the article claims that, above all, IS's rise constitutes a bid for increased power and influence vis-à-vis rival Islamist groups. By being the first one to venture building an 'Islamic State' of this magnitude and Islamic connotations, IS poses a direct challenge to other groups within the jihadi sub-system. The challenge is most direct towards the other jihadi claimant to a global brand, al-Qaeda. Al-Baghdadi assumed that al-Qaeda no longer fulfilled ISI's needs and that, after bin Laden's death, there was room for a new brand. At the same time, the diminishing levels of trust and communication, both exacerbated by geographic distance, deepened the rift. Access to new resources and recruitment opportunities in the Syrian conflict, o ffered ISIS the additional material incentives to disassociate itself from al-Qaeda.

Drawing on Watts's (2016) exploration of IS–al-Qaeda competition, the article shows that IS–al-Qaeda rivalry has taken the form of 'destructive' and 'escalating competition'. However, contrary to Watts, the article posits that destructive competition, in terms of direct conflict between al-Qaeda and ISIS has been in reality limited, even in Syria, where the two groups were in direct contact. Apart from some skirmishes and localized fighting, the lion's share of anti-ISIS violence came from local jihadi forces. Although the jihadi movement traditionally su ffers from weak institutions, high-level fighting between al-Qaeda and IS did not materialize, largely because the al-Qaeda leadership decided to keep a conciliatory tone in its 'war of words' against IS. At the same time, although ISIS often flirted with the notion of takfir against al-Qaeda, it crossed the line only in the end of 2015, when intra-jihadi fighting in Syria had largely ceased and the competition had shifted to global outbidding.

Instead, as the article shows, the rivalry between the two has been played out in three domains: propaganda, attacks on western targets and a 'war of bay'as'. The article, which mainly focuses on the latter, shows that the rift between al-Qaeda and IS forced prominent ideologues and jihadi groups around the world to situate themselves on the new jihadi map, either reiterating their loyalty to al-Qaeda or siding with the new-comer. This resulted in a flurry of competitive pledges of oath coming from all the corners of the jihadi movement. By initiating this 'war of bay'as' IS sought to create an arc of a ffiliates to claim a hegemonic role within the jihadi scene. IS expected little from its affiliates and gave little in return. Contrary to al-Qaeda, which expected its a ffiliates to fight the far enemy, IS was content to leave its a ffiliates to fight their local battles. Given that IS lacked the capacity to physically reach the entire umma, it chose to forge alliances with local same-minded forces that will carry its banner to the most remote corners of the umma. IS's international alliances materialized because IS and its a ffiliates do not compete in the same political and resource market.

In local contexts, however, the IS–al-Qaeda competition generated a cycle of intra-field rivalries and fragmentation. Most of the groups that pledged allegiance to IS were splinter-groups from established (often al-Qaeda a ffiliated) organizations. This local intra-field competition unwounded along old cleavages, regional di fferences or preexisting leadership disputes. In several cases geographical dispersal attenuated preexisting cleavages, festering poor communication and increasing intra-movement suppression costs. The motivations of local jihadi groups that pledged bay'a to IS run across the resources-ideology spectrum. Some groups were genuinely excited by the reestablishment of the caliphate, while others were driven by organizational concerns and (tangible and intangible) resources-related considerations, as the relevant scholarship predicts. Weakness, as result of increased (state) counter-insurgency and military setbacks, has been also at the core of some splits. A motivation shared by almost all groups was local political relevance and influence, especially for groups operating in competitive jihadi environments. This quest for local power and relevance was only marginally related to the al-Qaeda–IS competition, but it was exceptionally destructive for local conflicts.

Some alliances proved successful and lasting, while others, although announced with many hopes, were born stillborn (e.g., Algeria, Tunisia) or were quickly subsumed by their early successes (e.g., Libya and to some extent Yemen). IS's territorial losses in Syria and Iraq has taken a serious blow to IS brand. However, despite losing its capacity to 'remain', which has been the centerpiece of IS propaganda, IS manages to preserve most of its a ffiliates. The assassination of al-Baghdadi served an additional blow to IS, largely because the IS brand was built on a personality cult around al-Baghdadi. This renders the e ffort of his successor, Abu Ibrahim al-Hashimi al-Qurashi, to solicit support and authority harder (Bunzel 2019). Nevertheless, al-Baghdadi's death has instigated a flow of bay'a renewals from o fficial wilayat and a ffiliated groups (Zelin 2019), demonstrating that IS, although severely weakened, remains relevant.

**Funding:** This research received no external funding

**Conflicts of Interest:** The author declares no conflict of interest.
