It's a complex question with a complex answer. A lot of it depends on what kind of kid he is. If he's a rebel, he's going to do what he's going to do, steering him towards better quality and teaching use in moderation might be the most beneficial. Alternately, he might just need some good stern parenting and instruction. It all depends. Either way, there should be a conversation about substance abuse, as well as the difference between "using" nicotine, and the enjoyment of a fine cigar once a week.
What kind of marriage you have, how you two communicate, and his relationship with your wife will also have some bearing on your decision on how to proceed. Is she likely to support whatever decision you make, or is she likely to be against you encouraging any kind of smoking at all? The last thing a kid who is rebelling needs is divided parents, but if he's a good kid then teaching him moderation is really a valuable thing... if your wife supports it. If he's a rebellious kid, you and your wife need to be 100% unified.
Again, lots of options depending your your family situation, but I would talk it over with your wife. Come to a mutual agreement and present it to your kid.
Personally I'd explain to my wife my desire to teach my son how to enjoy life's pleasures properly, within bounds, and using self control, and then together with your wife (i don't mean it needs to be a "family meeting" or anything, just that you two should be in agreement) let your son know you are willing to let him enjoy the finer things in life, provided he does them only with you, and only in a responsible way and that there will be consequences for violating those rules. If done properly you could not only help teach your kid some valuable life lessons, but also gain a new avenue to build relationship with him.