Why Defeating ISIS in Mosul Took So Long

Last October, the Iraqi government and the international coalition fighting the Islamic State (ISIS) declared confidently that the battle to recapture Mosul would soon be over but it wasn’t until July that they managed to defeat the militants in the city.

The prelude to the battle to retake Mosul filled observers with confidence. An attack from all sides by different anti-ISIS factions – Iraqi government troops, Iran-backed Shia militias and Kurdish peshmerga forces – overran ISIS-controlled villages with speed and assurance.

Once the fighting reached the city and was limited to Iraqi government forces to lessen possible sectarian consequences, the offensive ran into difficulty, even though ISIS fighters were heavily outnumbered.

Gareth Browne, who reported extensively on the battle for Mosul, said: ‘The offensive has taken far longer than the Iraqi government had expected and was prepared for, more than twice the length it had initially claimed it would take’.

Browne offered numerous reasons for this setback, includ­ing a deficit of planning and a lack of tactical sense. ‘Initially, Iraqi tactics were naïve’, he said. ‘They focused their efforts and elite forces on one single axis of advance. This made defensive positions far easier to hold for the Islamic State, even with such a numerical disadvantage’.

The crushing advantage in personnel did not translate into a swift victory. ISIS fighters made use of the terrain. They created smokescreens and constructed barricades and other defences. The caliphate defended itself with deadly effect. Those fighters were left behind with instructions to inflict maximum casualties on Iraqi forces.

Browne said the government has had significant losses – up to 50 per cent in some cases – in some of its most capable fighting units.

Faced with these conditions and the prospect of the offensive stalling, the Iraqi government adapted its tactics. ‘As the fighting entered its second or third month, we began to see Iraqi forces advancing on multiple fronts simultaneously, notably from the east and south-east. This certainly helped overcome ISIS’s defensive capabilities’, said Browne.

At the same time, however, came a tactical decision with far-reaching consequences: As elite counterterrorism units such as the Golden Division began to take heavy casualties, Iraqi forces began to rely more heavily on air strikes by the US-led coalition.

Though these strikes were highly effective at killing ISIS fighters and destroying obstacles in front of the Iraqi advance, they could not do everything. Public buildings such as Mosul’s university were heavily defended. ISIS fighters fortified themselves inside and put up stiff resistance.

The air strikes were criticised for causing an increase in civilian casualties. This was only exacerbated when the fighting entered the narrower streets of west Mosul and the medieval Old City.

Nonetheless, Iraqi forces gradually extended their control over the city, though it is not entirely secure.

Reconciliation, however, is not going to be easy. ‘The prospects for transitional justice in Mosul are bleak, there are already widespread claims of war crimes against Iraqi forces’, said Browne.

These crimes will sour any attempts to foster pan-Iraqi unity and hurt the formation of a new, post-ISIS national identity.

At the same time, the chal­lenge of ISIS remains. It may have been deprived of its de facto Iraqi capital but its strength endures in the border region with Syria, where its leadership is likely to be gathering.

ISIS will retreat into the desert, adopting the tactics its predeces­sor, al-Qaeda in Iraq, used so effectively after it was rolled up by US-allied tribes in Anbar prov­ince and elsewhere.

There is a genuine military threat to be faced. Iraq must throw off the spectre of its failures in the face of ISIS’s initial advance in 2014 and the difficulties engendered in the caliphate’s defeat.

It would be too easy to allow Iran-backed forces to do the heavy lifting but the conse­quences of this could be disas­trous.

‘If it is to prosper, the country needs to rebuild its security capabilities quickly, but mustn’t compromise on quality or sectarian grounds’, Browne said.

This piece was originally published in The Arab Weekly.