The fundamental argument is that industrial cropping methods steadily denature soils until it becomes unusable. We are not there yet and GMOs are actually a way to postpone that day..
Salvaging those soils will mean a full return to organic methods augmented with biochar amendment in particular. I make the argument that we cannot start soon enough and will need access to human labor in particular to optimize the organic protocol. That will provide a mainstay for my economic redevelopment that ends poverty and provides a healthy life way for all humanity.
The process has begun and will likely take three generations to get right.
Genetically Modified Crops: The Trouble Is In The Soil
Supporters claim that GM is the only way to feed the exponential growth of our population in upcoming years. In this view sustainable agriculture is achieved by creating organisms that are able to grow and produce high yields despite disease and unfavorable conditions that do not allow their unmodified counterparts to. They also hold tight to the fact that there are no documented cases of that point to the harmful effects of GM products to humans.  Monsanto, the world’s largest supplier of GM seed, claims that they are the most vigorously tested crops in the history of agriculture, testing for nutrient retention, allergens, and gene safety, which is used as proof for safe consumption. 
What people decide to put into their bodies is their choice as long as they are able to make informed decisions; this does not affect other people. If GM supporters have no issue consuming carcinogens, then GM adversaries have no authority to tell them otherwise, and vise-versa. The issue here lies in tactics to conceal information and also make false claims on both the supporting and opposing sides.
However, the larger issues of GM reach far beyond the question of human safety into that of our planet, whose health we all depend on to survive. We cannot escape this fact, no matter how much yield comes from a field, or how many new medical procedures, and drugs we discover to prolong human life. As long as we continue to support GM agriculture, we are indirectly subjecting other people on this planet to the direct harm it poses to our environment. We will not survive if we turn our planet into an inhospitable environment.