Here's what I know but what most people don't appear to know.
I read Science News when growing up and well into my young adulthood. GMO based crops were introduced to feed livestock in the 1980s and even more in the 1990s to test the safety aspect of using the plants a food. They followed the lineage of upward of ten generations of livestock and tested vigorously using all the powers of science available to find any reason at all the associate GMO crops to health risks, both short term and long term. It wasn't until the scientists AND the FDA were completely satisfied that GMOs were safe as long as proper research and genetic knowledge of the plants were provided (due diligence) that they started testing on Humans, which was also performed for years before they were satisfied they were safe beyond any reasonable doubt.
Now, all that research, which is explained theoretically in scientific papers (but much of which is considered trade secrets the companies want to keep out of the hands of their competitors, and for good reason) is not accepted or known by the general public.
What these companies were trying to accomplish was to solve many of the major issues of traditional agriculture, like the out of control use of pesticides, herbicides, and fertilizers which were hurting our environment. They wanted to get more nutrition to people year round and reduce the amount of waste in rotten produce being tossed out because it would rot before it sold. They wanted to enhance the nutritional properties of common produce to make the planet healthier. And, by doing that well, they wanted to make money.
Most of these researchers and scientists did this work with an absolute belief they were helping mankind. Because they are - how many of you can remember the 1970s when the only way to get vegetables in winter was to buy frozen or canned. AND, when there were vegetables, there was little selection and often they were not very ripe or already rotten.
This hard work has already improved the nutritional health of our population.
So, the next question... why is GMO the most dangerous thing we face in the supermarket? For centuries botanists have cross-bred crops to produce tastier or healthier or greater yielding crops. Heck, the orange carrot is not natural at all, it was bred by botanists in Holland to honor their royal family. A by product of their breeding an orange carrot was that the carrot became healthier with more Vitamin-A and other good nutrient, a the time they didn't understand the concept of vitamins.
Botanists have used cross-breeding to take anti-fungal properties of one poisonous plant and added that property to healthy food crops we eat. It has been used to make tomatoes stay ripe longer. It has been used to increase the yield of corn, wheat, and other staples. Cross-breeding has made some crops drought resistant and less likely to be attacked by common swarming bugs.
In the GMO process, instead of experimenting with thousands of attempts to cross-breed one property from a foreign plant into the DNA of a food crop, they are identifying exactly what gene is responsible for that property and activating (or suppressing) it to get the results needed to solve a production, health, or satisfaction issue in the original crop. How is that so evil?
How many generations of tests need to be conducted on chickens, rats, monkeys and humans before the public will accept GMO for what the scientist hope it is? We are already talking about genetically altering humans to prevent cancer, birth defects, and even to get attributes which are purely cosmetic like blue eyes and large breasts. Somehow thousands of people using gene therapy is okay but altering the genes of a plant are not.
How long do the scientists have to invest billions of dollars in technology which may end hunger permanently or improve the health of humans around the world before we will accept their work and the research they've done?
We accept the junk science of bottled water being healthier than filtered tap water. We accept the idea that organic farming is inherently healthier than non-organic farming (there is a significantly higher risk of tainted food from organic farming). We accept eye surgery, cancer treatments, most medicines, medical imaging technologies, synthetic fabrics, and other magnificent advancements to the health and quality of life, but we refuse to accept this amazing technology which could help the world more than all the other things we do?
So, when does the jury come to a conclusion? I get the impression the "jury will be out" considering the safety of GMOs forever - or at least until the jury finds in favor of those who are convinced GMOs will kill us.