Ok...let's put some myths to bed.
MOST smokers don't get cancer. This is a FACT.
MOST passive smokers don't get cancer. This is ALSO a fact.
Red meat, drinking, processed meat (so no more bacon, ham, sausages etc) are all actually bigger causes of cancer than smoking. The link between obesity and cancer is FAR stronger than that between cigarettes and cancer. It is a one-to-one correlation, smoking is not.
The irony in all this is that smoking can cause a loss of appetite which may, in fact, lessen your risk of cancer. So I, as an occassional smoker with an incredibly healthy diet, doing at least 6 hours of vigorous exercise a week may actually have less risk of cancer than most non-smokers.
And yet we have smoking bans and militant non-smokers preaching all the bloody time. Alcohol kills more people every year but I'm sure we all remember what happened when the US tried to ban it.