We have arrived at a crossroads. Few can have believed that the bloody killings of Charlie Hebdo's staff would be the end of it. Today many may hope, but virtually no one will believe, that the ghastly attacks on the concert hall and restaurants in Paris will either be the end of it or, terrifyingly, the worst of it.
Since 9/11 and the wars in Afghanistan, Iraq and now Syria, and with so many other conflicts in between, instability has spread outwards and progressed ever closer towards us in Europe, while engulfing much of the Middle East and Islamic world in a fire which seems unquenchable.
In Europe there seemed to be a pause in the threat for a while after the attacks in Madrid and London, but Syria's descent into unimaginable carnage and the accompanying rise of Isis and their deliberate strategy to terrorise through deed and propaganda are a game-changer. The attacks in France this year have now brought this war to Europe. We feel under attack from without and within. People here in France have referred to last night's attack both as a civil war as well as war with the self-styled Islamic State.
Where does this end? How does it stop? What is fuelling this? Certainly the fight between Sunni and Shia fought between Iran and Iraq in the eighties casts a long shadow. It's been continued by proxy ever since, funded and encouraged by Iran and Saudi Arabia, and is seen right now in Syria, Yemen and Lebanon. Iran supports and arms and funds its proxy armies, and Saudi Arabia matches it in each country, but there is a fundamental difference. Isis are now a threat on a different level, either by deliberate plan or inspiration.
The causes of this spread of terrorism are complex, but one aspect we have to tackle head on -- its ideological roots in Wahhabi Islam, the official religion of Saudi Arabia. The House of Saud rules at the mercy of the clerics, some of whom see jihadism as a legitimate method of advancing their religion. The state in Saudi Arabia may not directly fund Isis, but the fundamentals of the Saudi state and society mean many of its people do.
The tenets of Islam have become distorted for too many believers. When I was a child I was taught about the Prophet, and about Mecca. My lessons contained no sense of threat. There was even a whiff of romance about it. But across North and West Africa, leaking into Europe; across the Middle East leaking into Afghanistan, Pakistan, India and now frighteningly newly, into Bangladesh, the intractable Wahhabi fundamentalist belief system is spreading fast. But "leaking" is a generous word. Radical Wahhabi Islam has not so much "leaked" as it has been exported, financed, and pushed into and beyond these countries.
It is not a movement that represented the majority of Muslim believers, but its spread and growth mean it can now appear as the strongest force within Islam - a force that is deeply attractive to alienated young people across the Muslim world and Northern Hemisphere. That sense springs both from the economic and social alienation many of them experience, and from a deep-seated resentment against the way Islam's holy places and the heartland of Wahhabism are managed. This explains, in part, why so many young Saudis have left and joined the so-called Islamic State. Indeed it explains why Wahhabi-believing jihadists joining Isis are revolted by the shopping malls and glitzy hotels that have come to dominate the holy cities of Mecca and Medina, located in Saudi Arabia, as they are by the Assad brutality backed up by Shia Iran and infidel Russia.
We in the West can do something to try to reach out to the economically and socially alienated Muslim. But tackling those alienated by the management of their faith in a far-away land upon which we are so dependant for both exports and imports of oil, is a far, far, greater challenge. We need to tackle the unending rivalry between Shia Iran and Sunni Saudi Arabia, which splits the region and fuels the violence. The war in Syria has been sustained and worsened by Iran's backing for a leader who started brutalising and massacring his own people the moment they demonstrated against him, and which has most recently been characterised by the routine barrel bombing of civilian areas. We may not blame Iran for the terror on our streets but many Syrians driven towards Isis blame them for the bombs on theirs.
We don't yet know the balance between internal French-based Islamic radicals and external Isis-centred forces, in the planning and execution of these latest atrocities in Paris. But we do know that Saudi Arabia has a problem, and it looks like the rest of us have little chance of being able to influence its resolution. The Kingdom is under threat from the very ideology upon which its twentieth century founders centered their entire philosophy and belief system.
The more the Royal family bows to Western demands for women's rights - car driving, voting, and the rest - the worse the confrontation with the Wahhabi zealots becomes. Indeed a recently retired British General, well versed in Saudi relations, told me only last week that if the House of Saud were to fall, the consequences for the world could be devastating. Yet there is a terrifying fusion between the Western resentment of the Saudi Royal Family's failure to modernise, and the Islamic State's conviction that the country's rules have already joined the ranks of blasphemers.
For too many young Wahhabi zealots across the Northern hemisphere, Isis had become the guardian of the "true way." Yet Saudi money continues to fund radical Wahabi preachers to establish Wahhabi radical Madrassas (faith schools) right across western Europe, North Africa and seamlessly through the Arabian peninsula into Afghanistan and the Indian sub-continent. What role any of this "export" played upon the distorted minds of those who loathed themselves enough to kill so many souls and then destroy themselves we don't yet know.
But we are now confronted by one of the gravest threats to our world and our way of life, since rise of the Nazism. We'd better start talking about it openly not only amongst ourselves, but with everyone with whom we relate who plays a role in its sustenance, and that of course includes the Saudis. They are increasingly themselves afraid of Isis, perhaps even more frightened of them that we are. Air strikes will not resolve what many Muslim scholars regard as a deep and insidious distortion of religious belief.
Indeed they may make it worse. Isis is winning converts with every passing day of war; Assad's brutality has created fertile territory. We may even have to start looking for other ways to engage with the self-styled Islamic State itself. Somehow the self-loathing, the hatred, and fear of others together with a fundamentalist commitment to a world that predates mechanisation, let alone digitalisation has to be combated. Governments in the northern hemisphere may have to be prepared to move aggressively to staunch the funding and manning of this terrifying movement. Pray God it is already not too late.
This post was first published on the Channel 4 News website on Jon Snow's blog here.