I like your libertarian approach. You're right the line can move a lot. Of course, my support/interference would (hypothetically speaking) be different on a situation to situation basis, my reasoning is simply love. If I love someone, like my son, I want them to be free to make mistakes and hurt themselves, and certainly if they start hurting others I would seek to stop that. I think it's important, though, to be there for people, nut the line does change like you pointed out. So I'm really not sure- my decisions would be situationally dependent. I'm still inclined to say that prohibition is ineffective and potentially more dangerous for some people