Except of course, that there is no provable harm caused by second hand smoke. If you say there is, then we can ban all sorts of stuff. For instance, BBQ's, lawn mowers, idling vehicles, chemical cleaning of decks, etc. The difference between tobacco smoke and these others is simply that some people have demonized the tobacco smoke, while the other types of smoke are still allowable. For now.
Do you really, honestly believe that? In 2006?
For instance, BBQ's, lawn mowers, idling vehicles, chemical cleaning of decks, etc.
Operating a BBQ indoors will kill you. Idling a car inside a closed garage is a favored suicide technique. Why do you think indoor cigarette smoking is the exception?