This Reason article on the growth of the nanny state in US municipalities confirms something which I have long suspected is the case, that very often a libertarian attitude towards illegal drugs is associated with an authoritarian attitude towards everything else. In fact the correlation between liberal laws on tobacco and liberal laws on illegal drugs is actually slightly negative (about -0.07).
Very few people or politicians adopt consistently libertarian or authoritarian principles, support for liberalising laws on drugs largely comes from those attracted to the counter culture attitude that the likes of marijuana exemplify. Equally support for allowing smoking in public places comes largely from those who view it as an established part of our culture rather than those who oppose state interference full stop.
Personally I think drugs probably should be legal and also oppose the increasing moves to outlaw smoking but principled libertarianism isn't the dominant outlook among advocates of either situation.
3 hours ago