The resounding successes of the Islamic State of Iraq and al-Sham (ISIS) in the summer of 2014 were shocking. Cities fell to ISIS forces a fraction of the size of their defenders; soldiers were ordered to abandon their posts; and those soldiers who were captured were massacred. Buoyed by its advance, the group declared a caliphate, a move that has split the jihadi world despite long being the aspiration of such organisations. Reeling from its string of defeats, it took until March 2015 for Iraqi forces to start their counter-attack in earnest, and even then, ISIS remained in a position to seize Ramadi in May 2015. But unprecedented as these advances were in scale, they fit into a pattern that the group has set since its foundation.
ISIS can trace its roots back to 2002, when Abu Musab al-Zarqawi – a Jordanian who was to gain notoriety in the Iraqi insurgency from 2003-6 – founded a jihadi organisation called Tawhid wal-Jihad in the north of Iraq. Zarqawi had been linked with al-Qaeda while in Afghanistan in the late '90s, but was not a member of the group and disagreed with the tactic of focusing on the 'far enemy' (the West) as opposed to the 'near enemy' (rulers in the Islamic world). Following the 2003 invasion of Iraq, Zarqawi's organisation grew more active and affiliated itself to al-Qaeda in 2004, becoming al-Qaeda in Iraq (AQI). Despite the tactical differences, this made a useful alliance of convenience: Zarqawi's organisation gained the recruiting and resourcing benefits of being part of a global and credible jihadi organisation, while al-Qaeda gained an affiliate in Iraq, already by that stage the global centre of jihad.
Zarqawi's AQI was an influential actor in Iraq's descent into chaos between 2003 and 2007. It had an explicit policy of stoking sectarian violence with the aim of rallying the Sunni community around Sunni jihadi groups, a tactic that ISIS is replicating now. This gained criticism from al-Qaeda's leaders, who felt that the indiscriminate and brutal violence risked alienating their supporters. However, it continued to support Zarqawi in public until he was killed in an airstrike in 2006.
In late 2006 AQI joined with eight other Islamist insurgent groupsto form the Islamic State of Iraq (ISI), without permission from the al-Qaeda leadership. The name chosen for this new group indicated its ambitions: it was more than a mere jihadi group, but an embryonic caliphate, governed by Islamic law, to which all Muslims within its territory owed allegiance.
As the US surge took hold in 2007 and the so-called 'Anbar Awakening' or sahwa – the cooptation of Sunni tribes in Anbar province in the fight against the insurgency – diminished the group's support base, the notion of the Islamic State's 'territory' was a tenuous one. Successive ISI leaders were killed in airstrikes, and the group's capacity to launch attacks was severely diminished. But the accession in 2010 of its current leader, Abu Bakr al-Baghdadi, coincided with a change in the external pressures the group faced. The USA withdrew its forces in 2011 and the promised integration of the Anbar militias into the armed forces was abandoned, removing a significant counter to insurgent activity. Absent American restraint, Prime Minister Maliki gave vent to his more sectarian impulses, creating grievances that the Islamic State was quick to exploit. Moreover, the start of the Syrian civil war created a fertile new cause and battlefield for the group's recruitment, and moulded it into the military force it has become.
The Syrian war also facilitated the Islamic State's final break with al-Qaeda. Since 2006, the group's relationship with al-Qaeda had been ambiguous, possibly deliberately so: the mutual benefits that had first prompted Zarqawi to affiliate to the organisation remained. In 2011, Baghdadi created a Syrian subsidiary, Jabhat al-Nusra (JN), under Abu Mohammad al-Jolani, in order to gain a toehold in the war. In 2013, with JN showing unwelcome signs of independence, he announced their reabsorption into the expanded Islamic State of Iraq and al-Sham – 'al-Sham' being the Arabic name for Greater Syria, with connotations of earlier caliphates. However, Jolani appealed to al-Qaeda's central command, which ruled in his favour, ordering Baghdadi to confine his group to Iraq.
The alliance between al-Qaeda and ISIS was no longer convenient. ISIS could now claim a history and a support base that established its credibility, and al-Qaeda's central leadership was weak. An ISIS spokesman declared that al-Qaeda's leader, Ayman al-Zawahiri, was sinful, and Jolani nothing less than a traitor. Shortly afterwards, Zawahiri announced that ISIS had nothing to do with al-Qaeda.
In subsequent fighting in Syria, much of it with other rebels including JN and other jihadi groups, ISIS gained and held significant amounts of territory. It captured the city of Raqqa from other rebels in early 2014, using it since as a base to launch attacks in Syria and Iraq. In Iraq, the group exploited botched Iraqi military operations in Fallujah in January 2014 to gain control of the city. Control of sparsely populated transport corridors allowed them to advance rapidly in the kind of surprise attacks that delivered them Mosul, among other cities, in June of the same year.
However, 2015 brought setbacks for the group, as Kurdish forces, comprising mainly the Popular Protection Units (YPG) in Syria and the Peshmerga in Iraq, emerged as key opponents. A hard-fought four month battle for the city of Kobane, on the Syrian-Turkish border, culminated in victory for the YPG in January 2015 – though ISIS maintained a presence nearby. In September 2014, the US began a military campaign against ISIS in Iraq and Syria, supported by more than a dozen European and Arab states. Extensive airstrikes have supported the operations of Kurdish and Iraqi ground troops in making strategic gains. In Iraq, the Peshmerga were able to dislodge ISIS from key areas around Mount Sinjar in December 2014. Furthermore, Iraqi security forces, aided by Shia militias supported by Iran, in March 2015 launched the first major government offensive against ISIS since June 2014, in Tikrit.
Throughout 2016, the group faced successive setbacks. In Iraq, the Iraqi army, supported by US-led air support and training, and the predominately Shia Hashd al-Shaabi militias gradually pushed the group back from the territories that it had captured in 2014, culminating in the October 2016 launch of an offensive to capture Mosul city. At time of publication, the offensive is ongoing.
Regardless of these defeats, ISIS' development since 2013 changed the nature of the group. It is no longer a mere terrorist group, but an army that can hold and administer territory. It governs according to harshly interpreted principles of Islamic law, including the imposition of dhimmi pacts on minorities – guaranteeing protection in exchange for the payment of a tax and the acceptance of second-class citizenship. Minorities, including Shia Muslims, have been subject to severe human rights abuses, including massacres and forced conversion, and the persecution of minorities in northern Iraq has been particularly brutal. ISIS has also provoked shock and condemnation worldwide for its brutal execution of foreign journalists and humanitarian aid workers, as well as captured combatants from opposing forces. While the quality of its governance is questionable – a 2006 paper produced by the group stated that improving the quality of the people's religion was more important than improving the quality of their lives – it can broadly coerce the consent of the people it governs.
Meanwhile, a further danger lies in the group's appeal beyond the borders of Iraq and Syria. While other jihadi groups, both in these countries and elsewhere, seek to establish an Islamic caliphate, ISIS claims to be one. Baghdadi has declared himself "Caliph Ibrahim," and goes by the title "Commander of the Faithful." In the language of his speeches and in his titles, he lays claim to a form of authority from the earliest days of Islam. This combined with the supposedly just cause of the fight against Assad in Syria has proved to be a powerful draw to young Islamists across the world, spread by means of an adept use of social media, and slickly presented propaganda such as the monthly magazine Dabiq. Some of these recruits will eventually return to their homes, taking with them their experiences as members of the most brutal jihadi group in the conflict.
By claiming responsibility for the November 2015 attacks in Paris and the downing of a Russian plane in Egypt, as well as numerous smaller-scale attacks in Europe, Africa, Asia and North America, ISIS gives the impression that the group, ordinarily focused on targeting the near enemy, is keen to convey a broadening of its operational strategy and the pursuit of targets further afield.
The danger is not limited to individuals attracted to ISIS' flag. In November, Baghdadi demanded that all Islamist and jihadi movements across the world be dissolved or absorbed into his 'caliphate.' Many groups have taken up the call, and new ones continue to do so. While some were previously unknown, others, including Boko Haram in Nigeria and Ansar Beit al-Maqdis in Egypt, have long been prominent actors in their own countries' conflicts. Moreover, the appeal of the universal caliphate is fracturing established groups that have not declared allegiance.
A focus on ISIS should not underestimate the unpredictable nature of this conflict: sudden changes in fortune have been a hallmark of the Syrian civil war, and in Iraq the concerted action of Shia militias and the military – not to mention Iranian interests – may yet turn the tide. Moreover, as the development of ISIS shows, jihadi groups can fracture suddenly and dramatically. However, bolstered by state-of-the-art equipment seized from Iraqi bases and resources from oil fields in its territory, by reported extensive assets, and by an Iraqi army that, whatever its current momentum, melted before them in June 2014, ISIS will not be defeated without a hard fight.
The US-led campaign against ISIS, known as Operation Inherent Resolve, has launched over 6,000 airstrikes against ISIS and is killing about 1,000 militants every month, roughly the same number believed to be joining the group, leaving the group's manpower strength effectively capped at 30,000 to 40,000. ISIS has had to adopt a different strategy since the commencement of aerial attacks on the group in Iraq and Syria, no longer having the freedom of movement it once enjoyed. With Russia entering the fray carrying out airstrikes against ISIS targets, the group's capabilities has been further diminished. As it progressively loses territory in Iraq and Syria, it will further change its strategies in order to survive.
This article was originally published on 17 June 2014. It was updated on 10 January 2017.