The bloody repercussions of the borders that the British and French diplomats, Mark Sykes and François Georges-Picot, drew in secret during the First World War – originally giving Syria, Mount Lebanon and northern Iraq to the French, and Palestine, Transjordan and the rest of Iraq to the British – are known to every Arab, Christian and Muslim and, indeed, every Jew in the region. They eviscerated the governorates of the old dying Ottoman empire and created artificial nations in which borders, watchtowers and hills of sand separated tribes, families and peoples. They were an Anglo-French colonial production.

The same night that I saw the early Isis video, I happened to be visiting the Lebanese Druze leader, Walid Jumblatt. “The end of Sykes-Picot!” he roared at me. “Rubbish,” I snorted. But of course, I was wrong and Jumblatt was right. He had spotted at once how Isis captured symbolically – but with almost breathtaking speed – what so many Arabs had sought for almost exactly 100 years: the unravelling of the fake borders with which the victors of the First World War – largely the British and the French – had divided the Arab people. It was our colonial construction – not just the frontiers we imposed upon them, but the administrations and the false democracies that we fraudulently thrust upon them, the mandates and trusteeships which allowed us to rule them – that poisoned their lives. Colin Powell claimed just such a trusteeship for Iraq's oil prior to the illegal Anglo-American invasion of 2003.

We foisted kings upon the Arabs – we engineered a 96 per cent referendum in favour of the Hashemite King Faisal in Iraq in 1922 – and then provided them with generals and dictators. The people of Libya, Syria, Iraq, and Egypt – which had been invaded by the British in the 19th century – were subsequently blessed with mendacious governments, brutal policemen, lying newspapers and fake elections. Mubarak even scored Faisal's epic 96 per cent election victory all over again. For the Arabs, “democracy” did not mean freedom of speech and freedom to elect their own leaders; it referred to the “democratic” Western nations that continued to support the cruel dictators who oppressed them.

Abd al-Wahhab demanded conformity -- a conformity that was to be demonstrated in physical and tangible ways. He argued that all Muslims must individually pledge their allegiance to a single Muslim leader (a Caliph, if there were one). Those who would not conform to this view should be killed, their wives and daughters violated, and their possessions confiscated, he wrote. The list of apostates meriting death included the Shiite, Sufis and other Muslim denominations, whom Abd al-Wahhab did not consider to be Muslim at all.

There is nothing here that separates Wahhabism from ISIS. The rift would emerge only later: from the subsequent institutionalization of Muhammad ibn ʿAbd al-Wahhab's doctrine of "One Ruler, One Authority, One Mosque" -- these three pillars being taken respectively to refer to the Saudi king, the absolute authority of official Wahhabism, and its control of "the word" (i.e. the mosque).

It is this rift -- the ISIS denial of these three pillars on which the whole of Sunni authority presently rests -- makes ISIS, which in all other respects conforms to Wahhabism, a deep threat to Saudi Arabia.

In a sense, Philby may be said to be "godfather" to this momentous pact by which the Saudi leadership would use its clout to "manage" Sunni Islam on behalf of western objectives (containing socialism, Ba'athism, Nasserism, Soviet influence, Iran, etc.) -- and in return, the West would acquiesce to Saudi Arabia's soft-power Wahhabisation of the Islamic ummah (with its concomitant destruction of Islam's intellectual traditions and diversity and its sowing of deep divisions within the Muslim world).

As a result -- from then until now -- British and American policy has been bound to Saudi aims (as tightly as to their own ones), and has been heavily dependent on Saudi Arabia for direction in pursuing its course in the Middle East.

In political and financial terms, the Saud-Philby strategy has been an astonishing success (if taken on its own, cynical, self-serving terms). But it was always rooted in British and American intellectual obtuseness: the refusal to see the dangerous "gene" within the Wahhabist project, its latent potential to mutate, at any time, back into its original a bloody, puritan strain. In any event, this has just happened: ISIS is it.