'Ah, but there is the difference. We knew it was propaganda,' replied Sacha.

That is the difference. Russian propaganda was so obvious that most Russians were able to ignore it. They took it for granted that the government operated in its own interests and any message coming from it was probably slanted - and they discounted it.

In the West the calculated manipulation of public opinion to serve political and ideological interests is much more covert and therefore much more effective. Its greatest triumph is that we generally don't notice it - or laugh at the notion it even exists. We watch the democratic process taking place - heated debates in which we feel we could have a voice - and think that, because we have 'free' media, it would be hard for the Government to get away with anything very devious without someone calling them on it.

It takes something as dramatic as the invasion of Iraq to make us look a bit more closely and ask: 'How did we get here?' How exactly did it come about that, in a world of Aids, global warming, 30-plus active wars, several famines, cloning, genetic engineering, and two billion people in poverty, practically the only thing we all talked about for a year was Iraq and Saddam Hussein? Was it really that big a problem? Or were we somehow manipulated into believing the Iraq issue was important and had to be fixed right now - even though a few months before few had mentioned it, and nothing had changed in the interim.

In the wake of the events of 11 September 2001, it now seems clear that the shock of the attacks was exploited in America. According to Sheldon Rampton and John Stauber in their new book Weapons of Mass Deception , it was used to engineer a state of emergency that would justify an invasion of Iraq. Rampton and Stauber expose how news was fabricated and made to seem real. But they also demonstrate how a coalition of the willing - far-Right officials, neo-con think-tanks, insanely pugilistic media commentators and of course well-paid PR companies - worked together to pull off a sensational piece of intellectual dishonesty. Theirs is a study of modern propaganda.

What occurs to me in reading their book is that the new American approach to social control is so much more sophisticated and pervasive that it really deserves a new name. It isn't just propaganda any more, it's 'prop-agenda '. It's not so much the control of what we think, but the control of what we think about. When our governments want to sell us a course of action, they do it by making sure it's the only thing on the agenda, the only thing everyone's talking about. And they pre-load the ensuing discussion with highly selected images, devious and prejudicial language, dubious linkages, weak or false 'intelligence' and selected 'leaks'. (What else can the spat between the BBC and Alastair Campbell be but a prime example of this?)

With the ground thus prepared, governments are happy if you then 'use the democratic process' to agree or disagree - for, after all, their intention is to mobilise enough headlines and conversation to make the whole thing seem real and urgent. The more emotional the debate, the better. Emotion creates reality, reality demands action.

An example of this process is one highlighted by Rampton and Stauber which, more than any other, consolidated public and congressional approval for the 1991 Gulf war. We recall the horrifying stories, incessantly repeated, of babies in Kuwaiti hospitals ripped out of their incubators and left to die while the Iraqis shipped the incubators back to Baghdad - 312 babies, we were told.

The story was brought to public attention by Nayirah, a 15-year-old 'nurse' who, it turned out later, was the daughter of the Kuwaiti ambassador to the US and a member of the Kuwaiti royal family. Nayirah had been tutored and rehearsed by the Hill & Knowlton PR agency (which in turn received $14 million from the American government for their work in promoting the war). Her story was entirely discredited within weeks but by then its purpose had been served: it had created an outraged and emotional mindset within America which overwhelmed rational discussion.

As we are seeing now, the most recent Gulf war entailed many similar deceits: false linkages made between Saddam, al-Qaeda and 9/11, stories of ready-to-launch weapons that didn't exist, of nuclear programmes never embarked upon. As Rampton and Stauber show, many of these allegations were discredited as they were being made, not least by this newspaper, but nevertheless were retold.

Throughout all this, the hired-gun PR companies were busy, preconditioning the emotional landscape. Their marketing talents were particularly useful in the large-scale manipulation of language that the campaign entailed. The Bushites realised, as all ideologues do, that words create realities, and that the right words can over whelm any chance of balanced discussion. Guided by the overtly imperial vision of the Project for a New American Century (whose members now form the core of the American administration), the PR companies helped finesse the language to create an atmosphere of simmering panic where American imperialism would come to seem not only acceptable but right, obvious, inevitable and even somehow kind.

Aside from the incessant 'weapons of mass destruction', there were 'regime change' (military invasion), 'pre-emptive defence' (attacking a country that is not attacking you), 'critical regions' (countries we want to control), the 'axis of evil' (countries we want to attack), 'shock and awe' (massive obliteration) and 'the war on terror' (a hold-all excuse for projecting American military force anywhere).

Meanwhile, US federal employees and military personnel were told to refer to the invasion as 'a war of liberation' and to the Iraqi paramilitaries as 'death squads', while the reliably sycophantic American TV networks spoke of 'Operation Iraqi Freedom' - just as the Pentagon asked them to - thus consolidating the supposition that Iraqi freedom was the point of the war. Anybody questioning the invasion was 'soft on terror' (liberal) or, in the case of the UN, 'in danger of losing its relevance'.

When I was young, an eccentric uncle decided to teach me how to lie. Not, he explained, because he wanted me to lie, but because he thought I should know how it's done so I would recognise when I was being lied to. I hope writers such as Rampton and Stauber and others may have the same effect and help to emasculate the culture of spin and dissembling that is overtaking our political establishments.

· © Brian Eno 2003

A longer version of this article will appear in the new literary magazine, Zembla. Weapons of Mass Deception by Sheldon Rampton and John Stauber is published by Robinson at £6.99