Saying you are "pro-GMO" or that "GMOs are safe to injest" is like saying you are "pro-chemicals" or that "chemicals are safe to injest". Both statements are too overly broad to be anything but ridiculous.
There are most certainly genetic splices that could result in lethal "food" crops. For example, we could splice in genes from a variety of poisonous mushrooms and probably get them to express the lethal chemicals in, say, a tomato. Has Monsanto done that? No, of course not, that would be foolhardy of them, and they are evil, but not fools. Might one of the thousands of genetic modifications in the food supply yield something with unforeseen consequences? Without sufficient study, it's anti-science to say it's settled one way or the other. (That's the kind of sufficient study that *has* been done on global warming, but cannot be done on "GMOs" as a whole.)
GMOs need to be validated at the lowest level, one change to one crop at a time, where we can see what individual changes to certain plants do to their growth, production, and edible safety. Then we can approve those changes. Is this kind of approval being done? Not in the U.S. it isn't.
All of the above ignores the fact that some genetic changes are made to make the plants resistant to certain pesticides or other poisons, which are then slathered on the plants as they grow. Let's blanket assume that those genetic changes have been vetted, researched, and approved, and are 100% harmless for human consumption. Are the chemicals the plants have been bathed in suitable for human consumption? Just how long and how hard do I have to wash the food to get those chemicals off? Are they absorbed into the food? Is a non-GMO version less likely to have toxic chemicals in it? (Can I get a non-pesticide version without having to swing all the way to the other extreme and buy organic?)
The fact that you make such broad, unprovable statements such as "Anti-GMO hysteria is anti-science" and call your opponents "anti-GMO zealots" completely ruins the rest of your reasonable argument about the need for genetic modifications to food staples to ensure an adequate global food supply in the 21st century.