In a blistering oration at the Oxford Farming Conference, environmentalist Mark Lynas tore into the opponents of biotechnology, describing them as "blinded by romantic nostalgia for the traditional farming of the past".
Looking at the issue from a planetary – and therefore considerably hungrier – perspective, Mr Lynas called on politicians and pressure groups to stop indulging their "aesthetic illusions" and forcing their anti-science agenda upon Third World farmers for whom biotech breakthroughs were the best hope of survival in the years ahead.
"I don't know about you, but I've had enough – my conclusion here today is very clear: the GM debate is over. It is finished," Mr Lynas told the Oxford audience.
"We no longer need to discuss whether or not it is safe – over a decade and a half with three trillion GM meals eaten, there has never been a single substantiated case of harm. You are more likely to get hit by an asteroid than to get hurt by GM food. More to the point, people have died from choosing organic, but no-one has died from eating GM."
Mr Lynas' uncompromising stance – first unleashed at the World Potato Congress in Edinburgh last year – has considerable credibility, as he was a self-confessed founder of the anti-GM movement back in the mid 1990s, and spent several years ripping up GM crops himself.
"As an environmentalist, and someone who believes that everyone in this world has a right to a healthy and nutritious diet of their choosing, I could not have chosen a more counter-productive path. I now regret it completely," he said.
Explaining his change of heart, Mr Lynas said that his campaigning on climate change had taught him the value of peer-reviewed 'consensus' science, alongside the frustrating experience of arguing with 'climate change deniers' who refused to listen to statistically supported evidence.
When he realised that his own anti-GM campaigning was equally 'anti-science', he was forced to reconsider his position – and has now emerged as the boldest public exponent of biotechnology in the UK.
"I did some reading. And I discovered that one by one my cherished beliefs about GM turned out to be little more than green urban myths," he recalled.
"I'd assumed that it would increase the use of chemicals. It turned out that pest-resistant cotton and maize needed less insecticide.
"I'd assumed that GM benefited only the big companies. It turned out that billions of dollars of benefits were accruing to farmers needing fewer inputs. I'd assumed that Terminator Technology was robbing farmers of the right to save seed. It turned out that hybrids did that long ago, and that Terminator never happened.
"I'd assumed that no-one wanted GM. Actually what happened was that Bt cotton was pirated into India and roundup ready soya into Brazil because farmers were so eager to use them.
"I'd assumed that GM was dangerous. It turned out that it was safer and more precise than conventional breeding using mutagenesis for example; GM just moves a couple of genes, whereas conventional breeding mucks about with the entire genome in a trial and error way," he asserted.
The challenge facing mankind was stark, said Mr Lynas. The welcome trend of reduced infant mortality in the Third World meant that 9.5 billion people will need to be fed by 2050, on about the same land area as was used today, using limited fertiliser, water and pesticides and in the context of a rapidly-changing climate.
"We need to produce more food not just to keep up with population but because poverty is gradually being eradicated, along with the widespread malnutrition that still today means close to 800 million people go to bed hungry each night – and I would challenge anyone in a rich country to say that this GDP growth in poor countries is a bad thing," he said.
"But as a result of this growth we have very serious environmental challenges to tackle. Land conversion is a large source of greenhouse gases, and perhaps the greatest source of biodiversity loss. This is another reason why intensification is essential – we have to grow more on limited land.
"It is not enough to sit back and hope that technological innovation will solve our problems. We have to ensure that technological innovation moves much more rapidly, and in the right direction for those who most need it."
But supposedly environmental campaigns spread from affluent countries had succeeded in making biotechnology prohibitively expensive to all but the very biggest corporations.
"It now costs tens of millions to get a crop through the regulatory systems in different countries," he reported. "In fact the latest figures I've just seen suggest it costs $139 million to move from discovering a new crop trait to full commercialisation, so open-source or public sector biotech really does not stand a chance.
"There is a depressing irony here that the anti-biotech campaigners complain about GM crops only being marketed by big corporations when this is a situation they have done more than anyone to help bring about.
"In the EU the system is at a standstill, and many GM crops have been waiting a decade or more for approval but are permanently held up by the twisted domestic politics of anti-biotech countries like France and Austria.
"France, remember, long refused to accept the potato because it was an American import. As one commentator put it recently, Europe is on the verge of becoming a food museum. We well-fed consumers are blinded by romantic nostalgia for the traditional farming of the past. Because we have enough to eat, we can afford to indulge our aesthetic illusions."
Mr Lynas had particular scorn for the "pernicious myth" that organic production was better, either for people or the environment.
"The idea that it is healthier has been repeatedly disproved in the scientific literature. We also know from many studies that organic is much less productive, with up to 40-50% lower yields in terms of land area.
"If you think about it, the organic movement is at its heart a rejectionist one. It doesn't accept many modern technologies on principle. Like the Amish in Pennsylvania, who froze their technology with the horse and cart in 1850, the organic movement essentially freezes its technology in somewhere around 1950, and for no better reason.
"There seems to be a widespread assumption that modern technology equals more risk. Actually there are many very natural and organic ways to face illness and early death, as the debacle with Germany's organic beansprouts proved in 2011. This was a public health catastrophe, with the same number of deaths and injuries as were caused by Chernobyl, because E.-coli probably from animal manure infected organic beansprout seeds imported from Egypt.
"In total 53 people died and 3500 suffered serious kidney failure. And why were these consumers choosing organic? Because they thought it was safer and healthier, and they were more scared of entirely trivial risks from highly-regulated chemical pesticides and fertilisers."
He noted that one of the commonest arguments against GM was that organic farmers would be 'contaminated' with GM pollen, and therefore no-one should be allowed to use it.
"So the rights of a well-heeled minority, which come down ultimately to a consumer preference based on aesthetics, trump the rights of everyone else to use improved crops which would benefit the environment."
Unfortunately, these antis now had the bureaucrats on their side, he noted, with Wales and Scotland officially GM free, "taking medieval superstition as a strategic imperative for devolved governments supposedly guided by science".
"Thus desperately-needed agricultural innovation is being strangled by a suffocating avalanche of regulations which are not based on any rational scientific assessment of risk. The risk today is not that anyone will be harmed by GM food, but that millions will be harmed by not having enough food, because a vocal minority of people in rich countries want their meals to be what they consider natural," he stormed.
"Farmers should be free to choose what kind of technologies they want to adopt," he insisted. "So my message to the anti-GM lobby, from the ranks of the British aristocrats and celebrity chefs, to the US foodies, to the peasant groups of India, is this. You are entitled to your views. But you must know by now that they are not supported by science. We are coming to a crunch point, and for the sake of both people and the planet, now is the time for you to get out of the way and let the rest of us get on with feeding the world sustainably."