Jean-Pierre Filiu, Professor of Middle Eastern Studies at Sciences Po in Paris, says Isis wants to “trigger violence against European Muslims” to fuel recruitment and their narrative of “them against us”.

Speaking in Dublin, Prof Filiu called for a coherent and strong European policy to tackle Isis and said the only way to defeat the terror group is through supporting local armed forces in Syria: “I think Isis is envisioning Europe far more European than Europe is.”

“For them, there is no border, just a question of opportunity. For them, the whole of Europe, no matter the cultural, national or historical differences, is the ‘home of the Jews and the Crusaders’ in their propaganda.” The author of From Deep State to Islamic State spoke to the Irish Examiner after he delivered a speech to the Institute of International and European Affairs.

He said Isis terrorists are very opportunistic. He said he understands Garda authorities rate the direct threat here as moderate: “Probably they are right, but the whole continent is threatened.”

And he pointed out: “You’ve had fellow citizens killed on the beaches of Sousse”, referring to the three Irish people murdered in the Isis-inspired massacre in Tunisia last June.

He said Ireland along with all other EU member states should take part in drawing up a more robust policy towards the Islamic State in Syria: “It is certainly a foreign issue [for Ireland], because it is over there. But it is a foreign issue that can have a deep impact on domestic policy and also where this society, like other European societies, are evolving.”

This includes, he says, the rise of Islamaphobia: “We cannot believe what is happening over there, will stay over there,” he said.

The historian and Arabist said a particularly dangerous aspect of Isis strategy is to drive a wedge within Europe against its Muslim population: “They want to trigger violence against European Muslims and every time Isis strikes in Europe what they want is civil war — civil war on a small or large scale, civil war because it will fuel recruitment and fuel their narrative of ‘them against us’.”

He likened Isis to a “postmodern cult”, one that is proficient in the use of media and propaganda: “Like all cults they have a coherent vision of the world and the chosen few are part of the vanguard.”

He said the actions of Russian President Vladamir Putin — through his indiscriminate bombing campaign — have “given a new intensity to the prophesy” and to Isis recruitment.

“They are saying ‘look, the whole world is against us and we are still winning, so the prophesy is happening.” As a French diplomat for more than 20 years, he said: “You can’t contain jihadi totalitarianism. If you don’t defeat it, it will expand and that’s what it’s doing — Isis is recruiting and expanding.”

Prof Filiu called for solidarity at EU level to “really tackle it as a European challenge”— and that a strategy and coalition similar to that after the 9/11 attacks is needed.

He said no war was ever won by aerial bombardment and said you need “local forces”, not foreign ones, as the latter is exactly what Isis wanted.