What I mean by harm is things like enacting economic policies which would do things like prevent the developing world from developing, resulting in people remaining in poverty. It's easy for healthy, happy, relatively wealthy people to say that we should cut emissions (cf. DiCaprio). But reality is that, if those people practiced what they preach, they'd be living in log cabins--without solar panels.

And I certainly take issue with your vegetarian example. What other people eat is none of your business. It sounds almost funny, but that would be food fascism--is there any other word for it? Do you really want some bureaucrat sitting behind a desk writing memos telling you what you are and are not allowed to eat? How can you think that's a good idea? The more governments try to control people, the more people are harmed. Doesn't history make this obvious? Why do people seem to think, "Yeah, but we can get it right This Time"?