Isil has created a lasting virtual presence that will continue long after the final shot is fired on the battlefields of Syria and Iraq, security experts said at a debate on addressing extremism.
As the last of the Isil fighters in strongholds like Raqqa are killed or captured, its continued appeal to misguided and disenfranchised young people comes into sharp focus, a Tabah Futures Initiatives talk in Abu Dhabi heard.
“Isil has showed the world what terrorism will look like in the future," Dr Naved Bakali, a research analyst at Tabah Foundation, an anti-extremism think tank, said of recent attacks in European cities.
"They have created this virtual space so even if they are losing physical territory, they will not go without a fight.”
“I don’t know how much longer they will be around, but their cause will be taken by other groups for sure."
Security services and governments across the globe are concerned about returning Isil fighters, but also, crucially, the group spreading its message to potential new recruits that have never been on watch lists.
This week, Malaysia's counter terrorism agency warned Isil was spreading images of Rohingya refugees with calls to fight a 'holy war' in Myanmar, while the British prime minister, Theresa May, said internet companies such as Facebook and Google had to do more to crack down on extremist content.
The suspects behind the London Bridge attack, which left eight dead dozens wounded in June, reportedly tried to recruit accomplices online, including an undercover BBC reporter.
Hicham Tiflati, associate researcher at the Resilience Research Centre in Halifax, Nova Scotia, said groups like Isil have an enduring appeal among young, frustrated Muslims with a sense that they and others have been subjected to injustice.
“Isil build all this appeal based on injustices and grievances, that we see as real, and these are mainly the root causes of violent extremism," he said.
“Even if we can convince and can work with young people to convince them not to sympathise or join Isil or any other group, it is very difficult for us to convince them to disengage from the ideology and to distance themselves from the grievances.
“So what we can do is we can work on the causes of grievances.”
Failed Arab Spring coups and arguable injustices in other countries, including France, where Muslim dress was in part banned in public six years ago, has played into the hands of those seeking new recruits, Dr Bakali said.
“A group like Isis becomes an attractive choice. They promote themselves as a Utopian Islamic state, plus they can offer a generous salary - it is the best funded terrorist organisation in history,” said Dr Bakali.
At its peak, Isis made up to $80 million a month, and likely several billion dollars since its formation.
“Isil helps recruits get married and pays dowries for their wives. For young widowed women living in extreme poverty, marrying an Isis soldier is an attractive option."
In 2004, the hijab was banned in public schools in France, and in 2011 on the niqab was banned in public.
“And a year ago there were attempts to ban the burkini, because they thought it was contradicting and alien to French society," Dr Bakali said.
“A large number of Female recruits to Isil have come from France, because they made women feel alienated. Isil recruiters to play off these identity issues.”
He said young people should be empowered and encouraged to engage in interfaith dialogue.
“We need to build bridges - and avoid heavy handed approaches,” he said.
“It is not to say religions are the same, but there are commonalities; we can find similarities between old and new testaments and the Quran and hadith literature, there are tonnes of similarities. If we come to together we will have a much more tolerant and cohesive society.”