That would be the precautionary principle, and we probably have good reason to want to apply it rather strenuously and control the spread of these.
But on the dual use component and renormalization, is it not really a get out of jail free card in essence for many smokers, because of the restrictions on where you can smoke conventional cigarettes? In fact, they can get their nicotine fix in areas where otherwise they wouldn't be allowed to smoke. So actually they use them where it's not convenient to smoke their conventional cigarette. They just use the e-cigarette then and use the other ones afterwards.