I think it would be banned, but as with many things in the past it would quite possibly be promoted for health benefits.
Smoking originally was.
Medical "knowledge" at the time had 4 components phlegm, yellow bile, black bile, and blood, these "humours" were then classified as Hot, Cold, Wet, Dry
Most medical conditions were seen as an imbalance of these.
Quickest cure was to restore the "Balance" by a dose of the opposite.
So if you had a fever, then a cold remedy would restore, and so on.
As t was "Hot" and "Dry" then Tobacco was seen as as a cure for many illnesses.