The Bill Of Rights were set up to protect us from anyone who would infringe on our freedom to say what we want, Be secure in our right to protection from anyone that might bring us harm (Gov. Or not), Our right to be secure in our homes from unlawful searches and having our things put up for auction because we decided we wanted to put substances in our bodies that happen to be illegal because there is money in it for the federal and local authorities to prop up their fascist burocracies
There's a reason that grown people are called adults, and not children. They can decide for themselves whether or not they want to do something, as long as it doesn't impact others in a negative way.
If someone wants to smoke, they have that right. It is their body, they should decide what they want to do with it. My opinion on what they do should not give me authority over their body.