Isis is facing near total defeat in Iraq and Syria – but it has been beaten and come back before

Jihadis have been preparing bunkers with weapons caches in the desert, ready to wait out the storm

Isis battled far longer than anybody expected for Mosul and Raqqa (Reuters)

Isis has fought desperately and skilfully to hold the Syrian city of Raqqa, under siege by Kurdish-led forces for more than four months, but will soon lose it in the latest defeat for the Islamic fundamentalist movement. Little is left today of the Caliphate declared in 2014, which once ruled most of western Iraq and eastern Syria.

Isis battled far longer than anybody expected for Mosul and Raqqa, but had to fight on multiple fronts against its many enemies and, above all, against the immense firepower of the US, Russian and allied air forces as well as conventional artillery. It was only by pounding large parts of both cities into rubble that the Iraqi security forces and the Syrian Democratic Forces (SDF) have been able to prevail.

Hard fought though the battles have been, there is no doubt who has won them and come out on top. Significantly, Isis has not put up much of a fight for Tal Afar west of Mosul or Hawija to the south, which were long term Isis strongholds. Only in Deir ez-Zor province on the Euphrates downriver from Raqqa are there signs that Isis has combat units capable of launching successful counter-attacks. One of these ejected Syrian government forces from Mayadin, a small city in eastern Syria in the last few days.

Governments around the world are asking about the completeness and permanence of the victory over Isis and whether the movement will try to demonstrate that it is undefeated by stepping up terror attacks abroad. Even if the role of Isis in these atrocities is by way of inspiration rather than organisation, they keep its name in the news and show that it still has followers willing to die for its beliefs.

One of the strengths of Isis at the peak of its success in 2014 was that it could fairly claim to have beaten better equipped and more numerous Iraqi and Syrian government forces through divine assistance. After losing most of its territory, this claim can no longer be made. Signs of falling morale are also evident in Hawija, where hundreds of Isis fighters and militants surrendered to the Kurds. This is not happening everywhere: in Raqqa only 15 Isis fighters have surrendered in three weeks.

Isis is suffering heavy defeats but it would be premature to believe that it is totally out of business. Its commanders will have foreseen that, however hard they fought, they would lose Mosul and Raqqa in the end. To fight on they have prepared bunkers, weapons caches and food stocks in the deserts and semi-deserts between Iraq and Syria where they can hope to ride out the storm and perhaps make a comeback in a few years’ time. Isis succeeded in doing this before, after being defeated by the US and anti-Isis Sunni Arabs in 2006-08 but returning stronger than ever after 2011 when the political situation in the region favoured it once again.

This might happen a second time as the unwieldy combination of different states and movements, which includes everybody from the US and Iran to the Syrian army, Hezbollah in Lebanon and the Iraqi Shia paramilitaries, begins to fall apart. Nevertheless a rebirth of Isis looks unlikely because its explosion onto the world stage over the last three years so shocked international and regional powers that they will be wary of allowing Isis to recreate itself.

Isis does still have strengths: the latest recording of its leader Abu Bakr al-Baghdadi indicates that he is still alive and, so long as this is true, it will be difficult to declare his Caliphate quite dead.

The ideology of Isis will live on sustained by the deep sectarian divisions between Sunni and Shia in the region, differences deliberately fostered by Isis massacres over the last three years. Some Sunni Arab youth whom Isis took great care to propagandise during its years in power will remain true to its cause. The very fact that so many Sunni majority areas have been occupied by Iraqi and Syrian government troops or militiamen may provoke disaffection among the Sunni population.

Nevertheless, winners and losers are emerging in the conflict in Syria and Iraq, though recognition of this may take time. The Kurds have done well out of the war, enabling them to establish the Kurdistan Regional Government in Iraq since 1991 and Rojava in Syria since 2011. The level of violence is also declining and this again weakens Isis, which functions best in militarised situations in which everything is decided by the gun. Isis may live on, but as a guerrilla force, always dangerous but not the mortal threat it posed in the past.