A shocking new film about the Islamic State in Iraq warns that the jihadist group is far from defeated and may return in an even more ferocious form.
Italian documentary makers spent 18 months talking to former IS child soldiers and the widows of its fighters for "ISIS, Tomorrow. The Lost Souls of Mosul", which was premiered at the Venice film festival Thursday.
What they found in the ruins of the destroyed city of Mosul, the second biggest in Iraq, was that the IS jihadists' violent ideology was very much alive.
If anything the commitment of the group's diehard followers has deepened, and the jihadists were looking to the generation of children they indoctrinated to take vengeance of the West and the Iraqi authorities.
"Today is yours, tomorrow is ours," the widow of one IS "martyr" who is held in what amounts to a prison camp for IS families, told the filmmakers.
A procession of young boys -- some of whom had lost limbs in the Allied bombing -- said they were still ready to die for IS.
- 'Blood and vengeance' -
"They are convinced that military and geographical defeat means nothing, so the indoctrination of children continues," said Alessio Romenzi, who began shooting the film with Francesca Mannocchi when fighting for Mosul was still going on.
"We will have to face the same problem again and again, even if it does not have the same name, because it has not gone away," he told reporters.
"What you cannot perceive from the outside is what motivates this movement or how deeply rooted it is."
Very few former fighters or IS supporters "have repented," he added.
One young former "Cub of the Caliphate" told how he dreamed of cutting the throat of American journalists just like Jihadi John, the British extremist Mohammed Emwazi believed to have been featured in several IS execution videos.
"Indeed, those who were loyal to that ideology are even more loyal," Romenzi said.
"What you feel in Mosul is a cry for blood and vengeance from both sides -- from the defeated and from those that have won."
The film shows an uneasy peace since Iraqi forces retook the city in July 2017, with an unknown number of suspected IS fighters -- many of them minors -- being held in horrific jails which some fear will be breeding grounds for an even more bloody insurgency.
Denied documents, medical care and schooling for their children, their families and supporters hide out amid the apocalyptic remains of their flattened neighbourhoods or fester in fury in tent cities where they have been left to rot
- 'We will kill them all' -
Mannocchi told reporters that she always got the same answer when she asked Iraqis how they were going to deal with IS as Mosul fell: "We are going to kill them all, what else can we do?"
By turning away and not helping to rebuild the city both physically and socially, the world risks reaping terrible consequences, she feared.
IS is "likely to come back with a ferocity and a violence we have not yet seen. It is not over. Iraq today is paying the price of the negligence and lack of understanding of what has even happened," Mannocchi told AFP.
"The US administration spent $14 million (12 million euros) a day on a war against terrorism to annihilate IS, but at the recent conference on rebuilding Mosul in Qatar, the international community walked away saying it was not its job to build countries. Yet they razed half the city to the ground.
"They were still bringing bodies out of the rubble 10 months after the fighting stopped and we still don't know how many civilians died in Mosul."
Mannocchi compared the situation to post-war Europe, when the Allies tried to de-Nazify defeated Germany, while helping it rebuild with the Marshall Plan.
But nothing is being done to counter IS brainwashing, she said.
"Fascist and totalitarian regimes have always given great importance to children," she said, with the Hitler Youth and Pol Pot's child soldiers.
IS leader Abu Bakr al-Baghdadi was still working on his school curriculum when Allied forces closed in on Mosul, she said.
In a purported new audio message to his followers last week he urged them not to give up.
"We need a social Marshall Plan to deal with this," Mannocchi argued. "IS is planning for the next 10 years and we are not."