It really is an incredibly awkward situation. It's terrible to condone or support something that has the potential to lead to an addiction with unknown ramifications. On the other hand, I agree with a couple of the other posters in that a child's behaviour is not necessarily indicative of parenting skills, and that it's incredibly difficult to monitor and restrict activities like smoking. I would be absolutely loathe to suggest my child start vaping because I know they smoke, and to then purchase vaping gear for them; however, not supporting their inhalation habit basically guarantees the child will remain with traditional tobacco products as vaping gear is usually too expensive and inaccessible for youths. I'm glad I'm not a parent.
I actually suspect that the increasing popularity of vaping should not impact the way parents have been handling situations like this for thousands of years; do your best to educate and steer your children in the right direction, and hope that they have the sense to limit self-destructive behaviour and make smart decisions regarding issues that matter.
My mother and father are bright, sensible, incredibly grounded, and pretty damn amazing. My mother exposed me to literature and theatre at every opportunity. They supported my love of speaking and music. My mother and I travelled from Australia to Europe when I was 16. I was able to visit Stratford upon Avon, and I'll never forget the Royal Shakespeare Company's performance of Coreolanus. I was school captain and topped five of my six senior subjects. My parents paid for my living and education expenses when I finished school and started studying law at uni. I smoked my first {OTHER STUFF} when I was 13. I drank my first bottle of whiskey around the same time. I lost my virginity at 14. From 15 to 17, my school days regularly started with a stop at a mate's house for a coffee, a cigarette, and {OTHER STUFF}. My parents are not stupid. I don't for one second imagine that they were completely ignorant of my extra-curricular activities, and nor do I believe they knew exactly what I was getting up to. I certainly don't consider their parenting skills relevant to my desire for a little extra fun, and I'm not sure what they could have done to suppress it even if they were completely aware. Perhaps they were lucky and managed to walk the tightrope. Maybe they knew exactly what they were doing, and what I was doing. Regardless, they are excellent parents, and I still got my nose involved in less than legal pursuits.
I am currently living in Korea, and vaping, while not as prevalent as in the States and Europe, still suffers at the hands of ignorance and media misinformation. Several schools in my area recently made announcements to their students that left them with the impression that electronic cigarettes are as harmful as traditional cigarettes, or near enough to it that the distinction is not worth making. The ramifications of good intentions spliced with half-truths and unfinished leaps of logic should be obvious, coming from such an institution of authority no less; students that smoked will continue to smoke, big tobacco will continue to bully them for their lunch money, and the dissemination of bull.... will continue.
I can also understand that ignoring the uptake of vaping by teens would be an unthinkable choice for parents and government organisations alike.
Marketing and education tactics for traditional tobacco products are simple and usually relatively truthful. The line is very clear. Vaping on the other hand, a term that my spell check does not recognise, is completely new ground for authority figures that are trying their best to guide our children to live healthy, successful, happy lives.
It's pretty damn difficult.