I think vegetarianism is necessary to obtain world peace. For humans to become more peaceful, the notion that humans are some sort of supreme, dominant, blessed creature must be dropped. This egotistical mentality extends to sex, race, religion, and even geographical proximity. This mentality creates enemies, causes wars, and might just be humanity’s biggest problem right now.
If some form of advanced extraterrestrial life came to earth and started harvesting humans for food, we wouldn’t appreciate that. Extraterrestrials could say something like, “Humans aren’t sentient”, or, “they can’t feel pain like we do”, or, “this is necessary for us to survive.”
When humans say the same things about cows, I’d have to disagree. I say animals eat other animals, which humans still are. I want humans to rise above that and become something greater.