But it comes down to this: nobody has ever or will ever grant me the authority to define right and wrong human behavior. There are extremes where most of us agree that stepping in and forcibly altering someone elses behavior is necessary, but this is allowed only by the fact that there are more of us than there are of them, not because we have, in any materially objective sense, some right to do what we're doing. I think you get a lot farther improving the world by setting a compelling and non-judgemental example.
But you really have to ask yourself, why do I care so much about some stranger's lungs? Or their taste in TV? Or honestly, given that they're one individual out of millions and millions, who they do or don't vote for. You're looking at a human being and only seeing incredibly trivial things.
I'm not talking about judgment. I have my opinion about certain behaviors and you are entitled to yours. But when your behavior costs me money, I think I should have a voice.
Is smoking morally wrong? I don't know or particularly care. If providing medical care for people who have health problems as a result of smoking costs public dollars, then the public gets a say about the legality of smoking.
Another example: I don't see anything morally wrong with being addicted to heroin. However, if you have to steal my TV in order to support your habit, I have the right to complain.
Sure, do what you want as long as you don't hurt anybody else. I just think people get awfully short-sighted when it comes to thinking about whom their behavior is indirectly (but demonstrably) hurting, especially when it comes to things like smoking.