The supreme court ruled that right to privacy does not apply if the activity is harmful to onseself. I've always thought that that was overly broad (there are an infinite list of things that we do that could be interpreted as "harmful" to oneself). As it stands, the government exempts tobacco and alcohol from drug laws simply because of their popularity, but it could ban them at any time.
If they were required to be registered as drugs, obviously, they'd be outlawed, because there's no recourse for something to be merely of recreational value, it has to be of medicinal value to be considered legal. For instance, Marijunia, which is safer than most over the counter drugs, is classified in the same category as Heroine because it has little medicinal value. I've always thought that drugs should be able to be legalized because of recreational value too - as long as they do not cause signifigant dependency or harmful effects in the average user.
Tobacco, however, presents a special case. It is very harmful, very addictive, and not even all that pleasurable. I've never really liked it. However, it's clearly not caused our society to fall apart, so I see little reason to ban it.
Kind of got off subject there, eh? Well, anyway, RS, I don't think that there can be a right to smoke.