Thanks for the range of opinions. I'll address some of the issues brought up in this post.
To begin, I did indeed mean "fetish." I first thought it to be that when I saw that word on one of the web pages that I saw he had visited. I thought it sounded strange, and I thought it was probably rare, but a Google search of "smoking fetish" turns up over 3.5 million pages (I guess for comparison's sake, I'd heard of the "foot fetish" before, and a search of that gives over 12 million hits). So, what worries me is that this is not just curiousity in trying smoking, but a sexualized interest in smoking. We have talked periodically (and in depth when he began high school) about the range of health, psychological, social, and economical issues surrounding smoking (and drug use as well), and I remember being relieved on multiple occasions (but not recently) when he reflected aloud that he doesn't see the risk and inconvenience as worth the rewards of smoking. But when I look at these fetish sites, some of them seem to emphasize things like the smell of smoke, stains on fingers and teeth, and even the hardships the smoker faces, like they're positive aspects... like they're something that is supposed to arouse the fetishist. Hopefully I'm being too paranoid here.
But I guess this brings me to another dilemma. Our parenting style has basically been motivated by the desire to turn our son into a happy adult. My husband and I were both saddled in our early adult lives by anxieties related to not having our parents there anymore to tell us in no uncertain terms what we should do in even the most trivial of situations. That is why we've been focussing on making sure he knows what there is to know about a subject, and letting him reason to his own decision. My husband and I both think, as far as we're concerned (though we recognize that there are people who will disagree), that there are more sources of unhappiness in smoking than there are happiness, and we thought our son thought this too. But if you throw in a sexual attraction to all the "good" things about smoking, and a lot of the "bad" things, I can see how his assessment might change. Hopefully he was just researching, but I have this feeling, call it "mother's instinct," that he was not.
So, I guess the dilemma is that even though I feel as if I should try as hard as I can to stop him from smoking, I ultimately just want him to be happy... so now I worry about how happy he will be if he feels the way I think he does about smoking but represses it all due to me actively trying to guide him as opposed to letting him decide for himself what to do with his life.