Tony Blair cuts a pitiable figure as he denies the self-evident connection between his violent occupation of Iraq and the barbarism being unleashed today. One of the great myths about the "moral imperialism" that Blair represents is that it consists of a simplistic, messianic faith in democracy. In this light, it is a problem of naive utopianism. This myth allows some of the critics of his war to get away with some extraordinary casuistry. As Isis racks up military successes in Iraq, the liberal newscaster Jon Snow argued, in head-shaking, tragedian vein: "History tells us repeatedly that extreme, violent, neofascist, religiously fuelled fanaticism has only ever been contained by secular tyrants. Decapitate the tyrant and the things fall apart – as in Iraq, as in Libya."

To parse this statement briefly, it is significant that Snow doesn't say what he evidently means, which is that this wisdom applies only "over there". The implied conceit is that secular dictatorship, while beneath "us", is good enough for "them". They – Arabs, Muslims – are so prone to "fanaticism" that labouring under a relatively enlightened elite is the best they can hope for.

The stakes in these discussions are extremely high. Obama has just sent 275 US troops back to Iraq, and it seems there may be an alliance with Iran in order to smash Isis. If Snow is right, presumably the only decent thing the US could do is help a new despot to power.

Ironically, though, he is far closer to Blair and his co-thinkers than he knows. For it was Blair who, when the dictator Mubarak was first threatened by Egypt's revolution, described the threatened despot as "immensely courageous and a force for good". It was he who, as the democratic crowds surged in Tahrir Square, warned that Egypt was characteristic of a problem in the Middle East where an "elite ... has an open-minded attitude" whereas "popular opinion" entertains "the wrong idea and a closed idea". He argued against aligning with the revolution, saying: "The danger is if you open up a vacuum, anything can happen." Blair's other favoured enlightened dictatorships included Colonel Gaddafi and the Saudi regime. About the latter he said, when challenged about its penchant for beheadings and limb amputations: "They have their culture, their way of life."

Blair is only the most strident advocate of this perspective. The US vice-president, Joe Biden, rallied to Mubarak's defence when his rule was threatened, denied that he was a dictator, and stressed that he was "an ally of ours". And the list of those who cosied up to Gaddafi is long. This is merely to scratch the surface of such complicity, which evinces not democratic messianism, but cultural condescension of the sort that has always characterised both liberal internationalism and the neoconservatism with which it shares a vocabulary. Blair and his ilk are not democrats, but liberals. For the people of the Middle East, they only favour democracy if it can help legitimise liberal capitalist regimes. But, like Friedrich Hayek when asked about his support for Pinochet, they prefer a dictatorship to a democracy lacking liberalism.

Snow's argument is complicit with these precepts in another sense. For, in his account, it appears that fanaticism was an already present reflex in the region. Accordingly, the growth of sectarianism, violent death squads and a mounting body count in the new Iraq is not traced back to specific policies pursued under the occupation – such as the installation of sectarian Shia groups into the state security apparatuses, the creation of the brutal Special Police Commandos, the construction of a corrupt, patrimonial state and the defilement of cities from Fallujah to Tal Afar. At worst, the invasion removed the lid on an already boiling cauldron of violence and rage and failed to put it back on.

As Alberto Toscano has shown, this trope of fanaticism has been a central motif of counter-democratic and imperialist ideology since the French revolution. Particularly, the notion that "native fanaticism" explains the turbulence of populations subject to imperial rule can be traced back to Britain's subjection of India, Egypt and Iraq. It was in these frontiers of empire that the idea of benign dictatorship for such apparently benighted peoples – "grandmotherly tyranny" as the Fabians liked to call it – was minted. And it was in the September-Erlebnis of 2001 – the rush to war – and its prolonged aftermath that the ancient thought categories of empire were ardently rehabilitated, helped along by orientalists and elite thinkers such as Bernard Lewis, Samuel Huntington and Robert Kaplan. The proof of the power of these ideas is that much of the opposition expresses itself in their terms.

The real problem with this ideology, then, is not its excessively sanguine faith in the masses, but its utter distrust of democracy. The problem with the invasion of Iraq is not that it removed a tyranny but that it was an act of tyranny; not that it freed the wrong people, but that it denied them their chance of becoming free. Iraq needed its Tahrir moment. What it got was Falluja – and now Mosul.