Ok, I'm going to break this down by argument here.
Protein.
I never said that I don't think you need protein. I said that you can get plenty from plants. My original post to OP was asking where the information came from, as I agree that you need protein to build muscle. Just not nearly as much as people tend to think.
Morality.
I'm under the impression that there is no moral way to kill anyone or anything that doesn't want to die. The only time I feel that it is morally acceptable to kill anything is to put it out of suffering that decreases quality of life to a point where it isn't worth it. So, yes. I believe it is immoral to kill animals for our consumption, as it is not necessary for our health and well-being.
Environment.
If you truly believe that we aren't stressing the earth by cutting down trees, producing unnecessary pollution and overusing valuable resources, I'm fine with not continuing this conversation with you. Your level of ignorance is beyond anything any of us could ever help. Here's a map explaining what I was saying.
https://www.vox.com/2014/8/21/6053187/cropland-map-food-fuel-animal-feed
Here's additional information on how much animal agriculture negatively impacts our earth.
http://www.onegreenplanet.org/animalsandnature/this-is-how-animal-agriculture-causes-deforestation/
Also, it's common sense (for most of us) that we, as humans, eat MUCH less than cows every day. To produce one pound of beef requires 12 pounds of grain to produce. I'm not sure about what kind of human you are, but 12 pounds of grain would feed me for much longer than one pound of beef. Before you try to argue this, remember that there really are starving humans all over our planet. Resources could be much better used by more people incorporating more plants into their diets. Here's some more information on sustainability here.
http://www.earthsave.org/environment.htm
And yes, pesticides are bad. I challenge you to find a single human who doesn't agree. That's why I try to buy organic every chance I can. This is when being vegan can become expensive (the point I forgot to make before). However, that's not because I'm vegan. If i were still a carnivore, I'd be trying to buy grass-fed, pasture-raised organic meat as well, which would be more expensive. That's the price we pay to help our planet, omnivore or not.
This leads me to your next point, that all agriculture is genetically modified and bad for our planet. However, our standards for food that is intended for human consumption are much higher than the larger amount of crops grown for animal consumption (see map I attached above). So if we're going pound for pound of pesticides and crap that enters our soil, more is being used for animal consumption.
Again, as much as I can afford it, I buy organic items. In all aspects of my life (soaps, detergents, cleaners, toothpaste, shampoo, etc.). So no, I don't like eating food that has been doused in chemicals. Most vegans, by default, are more aware of what they're putting into their bodies and buy organic anyways.
I don't see veganism as the only option for everyone. In fact, I've found some stats that say that flexitarians actually save more animals than vegans just due to sheer numbers. There aren't that many vegans around. Luckily though, many more people are seeing the health, moral and environmental benefits of plant-based foods and opting for those more and more option. Hopefully you can find a way to do that too. It's really the only way this planet will be able to keep going for future generations.
https://www.livescience.com/22814-meat-eating-vegetarianism.html
As for those who are on meat only diets, I'm sure they'll survive for a while. I sure as fuck wouldn't be okay knowing that I was providing my body with so few nutrients and such a small variety. You can't argue that you'd get the amount of nutritional variety you could on a plant-based diet. There simply aren't as many different forms of meat as there are plants. Not to mention the moral implications of knowing that something had to die EVERY time I eat. Disgusting. But that's just my moral standing and my opinion.