More than 400 million acres of genetically engineered (GE) crops have been grown in more than three dozen countries around the world. Plants produced in this way—also known as “genetic modification,” or GM—constitute the most rapidly adopted agricultural technology in history. Over three trillion servings of foods with GE ingredients have been consumed, and in almost 20 years of experience with GE crops, there has not been a single confirmed instance of harm to human health or disruption of an ecosystem.

There’s an old saying that absence of evidence is not evidence of absence so it is reasonable to ask whether harmful effects have been sought. The answer is a resounding, “Yes.” Hundreds of scientific risk-assessment studies performed around the world—including those funded by the highly risk-averse European Union—have failed to show harm from these crops; and after careful examination of the evidence, scientific organizations around the world have been virtually unanimous (and often effusive) in endorsing the safety (and utility) of GE crops and foodstuffs. In spite of all this experience, evidence, and expert opinion, anti-GE protestors still vehemently and steadfastly deny the safety and productivity of these crops.

Many wonder why the protestors carry on so enthusiastically—or as a law professor colleague of ours puts it, “the bastards never quit”—in clinging to discredited bizarre scare scenarios and resisting even public health breakthroughs that use genetic engineering, such as life-saving vitamin A- or iron-fortified crops. The motivations range from cupidity to stupidity, with several stops in between.

Perhaps the most fundamental objection is religious or spiritual—the conviction that genetic engineering is somehow unnatural and therefore unethical. Britain’s Prince Charles characterized it as venturing “into realms that belong to God, and to God alone.” That might explain why consecrated organic farmers place it in the same verboten category as chemical fertilizers and pesticides and synthetic growth hormones. Leaving aside the logic—or lack thereof—of the exclusions of those chemicals, the organistas ignore several salient facts:

1. with the exception of fish and shellfish, wild berries, wild mushrooms and wild game, virtually all of the organisms—plants, animals, microorganisms—in our food supply (including “heirloom” varieties) have been modified by one genetic technique or another;
2. because the techniques of modern genetic engineering are far more precise and predictable than their predecessors, foods produced with them are likely to be even safer than other foods;
3. virtually everyone in North America consumes food that contains genetically engineered ingredients daily, inasmuch as they’re contained in practically every product made with corn oil, high-fructose corn syrup or other corn products, canola oil, soybean oil or soy protein.

Some anti-genetic engineering activists object in principle to patents or plant variety rights for new, genetically engineered plant varieties. When farmers purchase genetically engineered seeds protected by such intellectual property rights, often they must agree contractually not to save and replant seeds from the harvest—much as the purchaser of Microsoft’s Windows software commits not to share it with others. Are such contracts evidence of the greed of big companies? Well, consider that seeds cannot be sold to farmers in the first place until the seed producers gain regulatory approval, variety by variety, trait by trait. The testing, documentation and approval process take years and can cost tens of millions of dollars per application. Is it greedy of the developers to expect a return on this investment? Still, there is no coercion in this transaction: Farmers who prefer not to pay the price of new seeds or who disapprove of the contractual restrictions can use older technology—not unlike the choices they have with farm equipment such as tractors and combines.

Economist and Nobel laureate Milton Friedman often counselled that in order to understand the motivation of an individual or organization, follow the self-interest. That applies here, because the lobbying by the organic industry reflects the influence of cynical self-interest—for example, the economic benefits to the organic farmers and retailers if they can undermine the development and commercialization of GE crops. The use of the technology to enhance the intrinsic pest-resistance of plants lessens the need for the application of chemical pesticides, threatening a salient selling point of organic foods—namely, that they are “grown without the use of synthetic pesticides and fertilizers.” Approved varieties of several major GE crops already have substantially reduced pesticide use, so this fear on the part of the organic industry is justified.

There is potent self-interest as well for the protest industry to incite hysteria about alleged or hypothetical risks of GE crops. Environmental NGOs such as Greenpeace and Friends of the Earth depend on donations and grants to fuel their multi-million-dollar international protest machines; mendacity, fear, and outrage keep the revenues flowing. These NGOs attack various targets according to their fear-mongering potential; scientific and technological progress and the public interest be damned.

The media play a key role in legitimizing even the most misguided anti-technology protest movements. The number and frequency of news reports about relatively benign activities and substances that appear under alarmist headlines are rapidly increasing. Desperate for higher ratings or more readers in an ever more competitive 24-hour news cycle, most media organizations still cling to the old editorial credo, “If it bleeds, it leads.” Every TV news director knows that a headline that elicits panic—“Poisons in your pantry? Report at 11!”—attracts more readers than one explaining that everything is copacetic, so explication often takes a back seat to sensation. And reporters and columnists often create a kind of moral equivalence, or false “balance”—often making it look as though opinions pro and con are equally divided in the scientific community, or playing off a scientist with a know-nothing activist as if the opinions of each were equally well-informed and supported by trustworthy evidence.

Many protestors against one technology or another are, in fact, ignorant about their cause but are guided by NGOs they trust. Ignorance is our right, after all. People can, if they want to, overeat, smoke cigarettes, and fail to take prescribed medications. They can also decide to be uninformed or misinformed about whichever public policy issues they choose. Unfortunately, that makes them vulnerable to being led to unwisdom, or worse. Consequently, there is a ready and willing army of street marchers, letter writers, petition signers and field-trial vandals, convinced that they are doing the “right” thing…because their leaders have told them so. Their main source of information is an interlocking, self-referential network of activist web sites, all pushing the same propaganda, drumming a repetitive message of mistrust and alarm into the woolly heads of their readership.

Marshalling logic and science to counter opposition to genetic engineering—and to many other life-enhancing technologies, for that matter—is a Sisyphean task. Economic self-interest, quasi-religious conviction and willful ignorance are hard to overcome, and the unreasoning are immune to reason.

Henry I. Miller, M.D., is the Robert Wesson Fellow in Scientific Philosophy and Public Policy at Stanford University’s Hoover Institution. A physician, he was the founding director of the Office of Biotechnology at the U.S. Food and Drug Administration. Robert Macgregor is an agricultural economist and wildlife biologist living in Prince Edward Island, Canada.