Was emphysema really due to tobacco smoke?

Most likely: In simple terms, emphysema means damage to air sacs in the lungs which leads to airflow obstruction. Tobacco smoke is most common cause of emphysema. Other causes include genetic (alpha 1 anti-trypsin deficiency), environmental (e.g. Air pollution), or occupational (toxic fumes from gases).

Yes: In the us the vast majority of emphasema patients have a smoking history (even pt with alpha1-antitypsin def - genetic disorder that causes emphasa, frequently only need treatment if they are also smokers). In the developing world many also develop emphasema from chronic exposure to biofuels ie. Coal/wood fire cooking in the home or industrially.