The reason for banning smoking inside buildings is simple. The smoke goes through the air in all directions and it gets inside the lungs of people who don't smoke and don't want to. It's a violation of their space. In that respect it is quite unlike alcohol. I don't get drunk because the guy next to me is drinking and my liver doesn't suffer from his habit. My lungs do suffer if the guy next to me is smoking (in a confined area).

Smoking itself has NOT been banned, Sorcha. It has simply been banned within confined public areas (buildings). And that's why.

And it was not banned inside anywhere because it's "enjoyable" either. This is not a killjoy operation. I DON'T enjoy it. No non-smoker enjoys it, and even most smokers don't enjoy breathing secondhand smoke coming from other smokers. I'd like to have a choice about the matter. If someone does enjoy smoking, as many do, they are perfectly free to do it out in the open air where the smoke can easily disperse. That is not a "ban".

A ban is when you don't allow people to do something at all.