My .02:
I used to smoke and would never have quit out of willpower. However, the summer I turned 17, the smoke from tobacco started making me sick. Headaches like butcher knives, nausea, cramps - I mean sick. I spent the entire summer traveling around, looking at colleges and so on, and trying one brand after another in the hopes of finding one I could stomach. Failed. Finally gave my last pack away and haven't smoked tobacco on purpose since. I have more respect for people that quit smoking out of willpower than probably any other group of individuals.
That said, it is still the case that tobacco smoke makes me ill. While I recognize any adult's right to make a personal choice to engage in fun and dangerous behavior (I am anti-seat belt and -bike helmet legislation, for instance, though I, personally, wear both and insist my children do), I also strongly feel that it is the responsibility of the adult in question to ensure that their choice remains personal. Thus you have a right to own a gun, you don't have the right to shoot me. You can wear no helmet, but don't sue me when it's my sidewalk your skull impacts. You can smoke, but produce no smoke around me. I won't even let my mom (still 5+ packs/day, over 70, and going strong) smoke in my house. She says, I drive a car, what's the diff? My answer: When I drive my car in your house you can smoke in mine.
Wish I knew a song about this - how about Live and Let Die?