Ahmed Ali, Jessica D. Lewis, Kimberly Kagan
ISIS has advanced from Mosul, which it seized on June 10, to take control of Tikrit, the capital of Salah ad-Din Province, Baiji, and the Baiji oil refinery. As of June 11, 2013, ISIS forces have also fought the ISF in Abu Ghraib and Zaidan west of Baghdad, further demonstrating the group’s capacity to manage simultaneous operations by multiple subordinate commands. Unconfirmed reports indicate that ISIS also conducted a second attack on Samarra, where retreating ISF forces from Tikrit have reportedly concentrated. ISW cannot assess the degree to which ISIS has moved to control the town of Samarra or to attack the al-Askari shrine as of 2300 EDT.
ISIS operations around Samarra during this phase of its northern offensive will be an important indicator of its ultimate intent and its estimate of its own capabilities. If ISIS means to continue a blitzkrieg offensive toward Baghdad it will likely need to bypass Samarra to maintain momentum and conserve forces. But Samarra is extremely significant in itself. Al-Qaeda in Iraq’s destruction of the al-Askari Shrine in 2006 ignited the sectarian civil war that had been simmering before then. Prime Minister Nouri al-Maliki will surely feel a great deal of pressure to prevent a repetition of such an event and may well attempt to concentrate forces to prevent it. Iraqi forces, militias, and Iranian proxies have long been in Samarra precisely to protect the shrine. ISIS could therefore attack the shrine for any of several reasons. It could seek to draw the ISF into a meeting engagement in hopes of defeating arriving ISF troops piecemeal. It could intend to destroy the rebuilt shrine to inflame the sectarian war even further. It could even find irresistible the prospect of fighting the actual Iranian forces and proxies thought to be in the city. Any or all of these conditions could lead to a major battle in Samarra, or the ISIS command might instead decide to bypass the shrine and continue south.
ISIS leaders might also believe that they have sufficiently disrupted and softened-up ISF and militia forces in Samarra to make an attack relatively easy. ISIS has been testing the Iraqi Security Forces and municipal buildings, of Samarra since mid-March through VBIED attacks, complex attacks, IEDs, and driving armed vehicles through the city. ISIS also burned thousands of acres of crops in the vicinity in May. The previous ISIS attack on Samarra on June 5, 2014, which preceded the northern offensive for Mosul, may also have been intended to disrupt Samarra’s defenses in advance of the arrival of the main body from the north.
Still another reason why ISIS might conduct additional attacks on Samarra could be in order to divert ISF attention from other operations. A major fight in Samarra risks bogging ISIS down and causing its advance to culminate prematurely – unless it has operational reinforcements.
But ISIS may very well have operational reinforcements. Fallujah and Jurf as-Sukhar, its strongpoints in Anbar and Babil, have been relatively quiet since the widespread ISIS operations began on June 5. Therefore, ISIS could be attacking Samarra in order to draw ISF and reinforcements there, while maneuvering from the Anbar or Babil axis of advance (or both) toward Baghdad. VBIED attacks against Sadr City and Khadimiya (home to another important Shi’a shrine) could be diversions, tests, or efforts to soften up the defenses in Baghdad.
It appears so far that ISIS is pursuing a well-planned and well-prepared deliberate offensive operation, rather than simply exploiting the collapse of the ISF in Mosul in a pell-mell advance. We have seen that ISIS has the capability to plan and conduct complex operations before. We must consider and be prepared for the possibility that additional ISIS attacks will unfold over the next 96 hours with the aim of completely disrupting and unhinging the ISF, even if ISIS is unlikely to be able to seize and hold Baghdad.
ISIS has never launched an offensive this expansive in Iraq. It is very possible that it could fall prey to the over-exuberance normal for a military seeing success beyond its dreams. ISIS could be over-extending itself, in that case, making it vulnerable to rapid counter-offensives or even to the rise of angry citizenry in its rear areas—a phenomenon that we have already begun to see to some extent in Mosul and that is well-known in ISIS’s main Syrian base in ar-Raqqa. But ISIS has also conducted sophisticated, multi-phased maneuver campaigns in Deir ez-Zour, Syria, showing its capability of integrating deception operations with movement in order to seize its objectives.
The most important question we must answer to understand whether ISIS is pursuing a well-laid plan or is pushing its luck too far is whether the same ISIS forces are moving from location to location, or are prepositioned forces being activated for simultaneous advance? This question is critical to understand the size and composition of ISIS’ force involved in the northern campaign. Reflections from the ground indicate that ISIS attacked Mosul with 150 vehicles armed with mounted crew-served weapons and between 500 and 800 troops. It is unclear if elements of this same force moved on to take Sharqat, Qaiyara, Baiji, and Tikrit, or if separate forces already proximate to these locations simply moved in to take their respective targets in sequence. ISW is actively searching for indicators of how ISIS attacked and seized control of these cities in order to answer this question. If ISIS had pre-positioned forces, then these forces likely now occupy their current target zones, which would allow the ISIS advance to continue.
If instead ISIS is seizing a city and establishing a leave-behind force while the assault force maneuvers, then the offensive is likely to culminate before it reaches Baghdad, depending on the nature of the force left behind. Is ISIS forming relationships with local tribes to help hold their newly acquired cities? Are recently released prisoners with little training part of that force? To what extent has ISIS made common cause with the Ba‘athist forces under former Saddam General Izzat Ibrahim al-Douri and the Jaysh Rijal al-Tariqa al-Naqshabandia (JRTN)? Reports indicate that JRTN forces and al-Douri supporters are active in Mosul and Tikrit, but we are not able to assess the extent of this activity with any confidence at this point.
It should be possible to assess in the next 24-48 hours whether the current ISIS offensive will continue uninterrupted or whether there will instead be a pause while ISIS regroups and consolidates. The level of activity in the areas northwest and southwest of Baghdad will likely be the most important indicator to watch.