A few years ago, I was talking with Al Gore (yes, I'm name dropping). I asked him a very simple and pointed question: "Animal agriculture contributes about 18 percent of the gases that cause climate change. Why didn't you mention this in your book or movie?"
His answer was disconcertingly honest. I'm paraphrasing, but he said: "For most people, the role of animal agriculture in climate change is too inconvenient of a truth."