Well i don't know much about Britain, but I would have to imagine that a significant percentage of lung cancer cases were not smokers... industrial workers, family members of smokers ect... and in any event, when you think about, most if not all disease has its roots in some form of "bad" behaviour. its all relative after all. one person smokes, another eats fast food, another does no exercise, another engages in risky sex. so, if we were to play the blame game, it would apply to all ill people. not very helpful at all.