Does this sound familiar? The Government - led from the front by the Prime Minister - has vigorously pursued a controversial policy, bitterly opposed by most of the British people. The supporting evidence is weak to non-existent, but the policy pleases President Bush and stands to benefit big multinational companies. Tony Blair believes unshakeably in the rightness of his cause, and in the folly of opponents who warn of unforeseen consequences. Then the truth starts seeping out. The facts turn out to be the opposite of the case that has been so eloquently talked up. Public opposition increases. But there is no U-turn, no reverse gear, no admission that Mr Blair might ever have been mistaken. Instead there is an attempt at damage limitation, a concentration on saving face, and a quiet search for a way out.
As with Iraq, so with GM, it seems. A succession of government reports critical of the technology over the last months - culminating in last week's publication of the results of official trials proving that GM oilseed rape and sugar beet damage wildlife - have become the equivalent of the failure to discover Saddam's weapons of mass destruction.
Virtually no one, supporters and critics alike, expected the reports to come down against GM, any more than they expected the weapons to be a mirage. Yet, like the non-existent WMD, they have changed the terms of the debate. And just as Britain and America have begun to secure agreement at the once-despised UN over the future of Iraq, a bewildering plethora of Whitehall committees are starting to try to find a way out of the Government's self-made GM morass.
The analogy is tempting, and can be extended. Both over GM and the Iraq war, of course, opposition to the disastrous policy has been led by The Independent on Sunday. GM even has its Dr David Kelly, in Dr Arpad Pusztai, another quiet scientist, respected as the world's leader in his field, who was belittled and persecuted when he challenged the official line. After a few incautious but accurate words to a broadcaster about research that was unexpectedly turning up alarming signs of damage to health in rats fed GM potatoes, Dr Pusztai was driven from his job, his data was confiscated, and he was roundly and unfairly denounced by the political and scientific establishment. He suffered a heart attack. Happily, he survived.
But there are also important differences. For, over GM, the truth has begun to stream out before the damage is done - at least as far as Britain is concerned. And the weight of evidence that is now emerging may yet be enough to prevent it occurring altogether.
Not that there is much change to be seen on the surface. Ministers are publicly saying much the same sort of things as they did last week, last month, and last year. Not even the faintest flutter of a white handkerchief has been spotted at the windows of No 10.
"I keep listening for the sound of rowing backwards," one senior civil servant told me last week. "But the oars are silent." At least the boat is not moving forward. The rowers appear to be resting on their oars wondering what course will now be steered. There have been such pauses before. It is easy to forget that, despite the Prime Minister's evangelism, despite his professed readiness four years ago to feed GM foods to his children, and despite all the spin and subterfuge, the Government has so far acted quite cautiously.
When Labour came to power, the biotech industry was on the verge of victory. Several GM crops were ready to go into British soil, and there was little public opposition. Monsanto - which last week inelegantly announced its intention "to exit from its European cereal seed business" in frustration - was riding high.
Days after the change of government, senior civil servants at the old Ministry of Agriculture, Fisheries and Food tried to get the new ministers to sign off well-prepared papers that would have uncritically endorsed the technology, and started the approval process for the crops. To their credit the ministers - Jack Cunningham, Elliott Morley and Jeff Rooker - refused. Morley, Rooker and Michael Meacher, the then environment minister, next pushed for a moratorium on the planting of the crops. As public opposition grew, they secured it in the three-year trials that reported last week.
The price was that the trials would ignore the main danger - that genes from the GM crops would spread, creating superweeds and contaminating their organic and conventional counterparts nearby - and concentrate instead on the narrow issue of how the different herbicides used on the crops would affect wildlife. The biotech industry boasted that spraying GM crops would be less damaging than treating conventional ones. It believed its own propaganda enough to agree to the trials, confident that they would clear their products. Pro-GM ministers believed this too, and so promised to abide by the results. And so did the environmental activists - so much so that they tried to wreck the trials.
Last week proved them all wrong. The results showed that growing conventional oil seed rape left five times - and conventional sugar beet three times - as much of the weed seeds on which many birds depend as the GM varieties. Both were also better for butterflies. Only GM maize did better than its commercial counterpart. But as The Independent on Sunday revealed last week, this was only because the traditional crop is predominantly sprayed with a particularly nasty weedkiller, atrazine, now being banned across Europe. The scientists admitted that this made the favourable verdict on GM maize "inapplicable", and senior government sources privately concede that more tests would have to be done before the modified crop could be considered for approval.
So where do we now stand? And where does the Government go from here? The environmental hazards of the modified crops are now clear. The trials - which collected more than a million seeds and more than one-and-a-half million insects - were the biggest experiment of their kind ever undertaken anywhere in the world. Few will challenge their thoroughness: even Roger Turner, chairman of the biotech industry body, SCIMAC, last week called them "fabulous".
Less noticed, another government study reported last week that growing GM sugar beet would drive the skylark to extinction within two decades.
But the now incontrovertible evidence that growing at least GM oilseed rape and sugar beet damages wildlife is perhaps the least of the environmental problems. Study after study around the world over the last few years has shown that the modified genes will inevitably escape from the GM crops. Yet more government research published last week showed that genes from GM oilseed rape could travel more than 16 miles and that growing it for just one season would contaminate the countryside for more than 16 years.
An official science panel chaired by Tony Blair's chief scientific adviser, Sir David King, was expected to endorse the technology this summer. Instead it concluded that it would be impossible to prevent this spread, at least for some GM crops. Senior ministers are coming to accept this. More important, they are also convinced - despite the Prime Minister's repeated past trumpeting of the importance of GM to Great Britain plc - that current modified crops will confer no economic advantage to Britain. This crucial change of heart follows yet another unexpected conclusion of a government study. In July a report by Mr Blair's own Cabinet Office said it could find no significant economic benefits from the current crops for the country or consumers.
Senior ministers, however, continue to delude themselves over the even more vital issue of possible health dangers from GM foods. They say that Americans have now been eating modified food for years without showing any ill-effects. But even the official Food Standards Agency, which has been criticised as a cheerleader for the technology, has warned that this argument is unreliable. Most health effects of concern - including cancer and the results of long-term damage to the immune system - would take years to become evident. Even then they would be hard to detect among the incidence of the diseases resulting from other causes. Only something startlingly new, such as new variant CJD, shows itself clearly. But, even so, ministers could - and did - say that Britons had been eating BSE-infected beef for years without ill-effects, right up until the moment that they had to backtrack.
Here the jury is not so much out as never empanelled. Almost no serious independent studies have been done on the hazards of GM foods. The most important, the work done by Dr Pusztai, was shut down as soon as he reported that it was demonstrating cause for concern. In the absence of evidence, the authorities in the US and Europe merely assume that GM food is substantially the same as its conventional counterparts and wave it through. But, until this week, the same authorities thought they knew that GM farming was beneficial for wildlife. A proper research programme might, again, overturn establishment wisdom.
Anyway, the public has decided not to take the risk. Only 8 per cent of the people responding to the Government's official consultation published last month said they would be happy to eat GM food. Ministers accept that there is "no market, no demand" for it whatsoever. The exercise also demonstrated massive public distrust of the Government. Many suspect that ministers had already decided to approve GM agriculture, and cynically used the so-called "debate" to try to win Britons over. A year ago that was probably true. But over the last months - perhaps chastened by their experience over Iraq - ministers from Mr Blair down have played it surprisingly straight.
So, what's the plan now? After last week GM oilseed rape and sugar beet will almost certainly never be grown in Britain. But ministers have been hoping to get away with approving GM maize. Its genes spread less readily than other GM crops and it appeared to be cleared by the results of last week's trials. Approving it would save the Prime Minister's face, and avoid annoying the US - while lack of demand might ensure it was never actually grown. Last weekend's report in The Independent on Sunday - that the maize results were invalid because they depended on atrazine - undermined this strategy. One Cabinet minister accused us of "moving the goalposts - again".
The temptation now will be to slow everything down, in the hope that public opposition will abate. The results of the crop trials have to go to the official Advisory Committee on Releases to the Environment. The committee will suffer some well-deserved embarrassment, as it blithely approved the particularly damaging GM oilseed rape a few years ago. But it will now find it hard - if impossible - to avoid recommending a ban on the rape and the sugar beet, and more research on the maize.
The Government could then legally announce the bans, a move that would almost certainly be followed by most European countries. Instead it is likely to drag its feet by plunging into the Byzantine maze of the official European GM approval process. This would be serious, because time is important.
Increasingly giving up on Europe, the biotech companies are focusing their attention on the rest of the globe, particularly developing countries. GM crops are now grown on more than 150 million acres of land in 16 countries - and last month Brazil, one of the most important hold-outs, finally gave way.
If Britain, and Europe, quickly make it clear that they will be GM-free, that will provide an important incentive to other countries to do the same, so as to be able to export their produce here. But if Europe delays it could find its own options narrowing as it becomes an island in a GM sea.
Already the biggest soya exporters - the US, Brazil and Argentina - have now all embraced the technology, making it harder for Europe to get the GM-free vegetable for the vast numbers of food products that use it.
So, just as over Iraq, inertia and a desperate desire to prove the Prime Minister right and avoid offending George Bush threaten seriously to damage the vital interests of the British people. It is time to decide where the true priorities lie.