I tried a different approach
Dear Mr. Atkinson
As you're no doubt aware of, your email adress has been publicised on a very popular website for hobbyist gamers. I can imagine that this will have led to a not inconsiderate amount of various emails written with the sole intent to harass and maybe even intimidate. For my own part I consider this a good opportunity to voice my disagreement in a more civilized fashion. Although I doubt that you'll ever read this, as this message is more than likely to drown in the ocean of other messages already pouring into your inbox. Still, it's worth an attempt.
As a gamer of grown age I've followed the debate on violence in videogames over the years and like to believe I have managed to remain somewhat unbiased on the issue (I do however enjoy several of the titles that have been given an 18+ rating, so my neutrality on the subject can be questioned), after all you have to know the subject matter to be able to make a balanced decision on any subject. In my experience there exist among us hobbyists (or childish, asocial nerds to some) a general consensus that yes, there are strong arguments that point towards a connection between violence in games and desensitization towards violence among minors. This should not be confused with the wrongful assumption that violent videogames leads to more violence, but it's pretty easy to understand that if a child is exposed to a great deal of graphic violence this will have an affect. However, this is no different to violence in films or books. Yes, the violence is interactive. Yes, you participate. And yes a lot of the violence is childish and sadistic. Violence in horror/slasher films is equally sadistic (take the "Hostel"-series as an example). A lot of great novels carry pretty graphic depictions of violence and sex and not always in a fashion generally considered moral or constructive. Yet, these mediums are accepted as entertainment because they were made for an adult audience, and not with children in mind.
I do believe you understand where I'm going with this and you've probably heard it before but remain unconvinced. Alas, it can't hurt to say it once more. Not all videogames are made for kids. In fact the term videogame is misleading and should be replaced with "interactive entertainment" or something similar. Videogames can be a form of art (I strongly suggest that you check out the game studio Tale of Tales with their titles "The Path" and The Graveyard") where themes such as death, sex and violence is given context. To deny these titles the right to be distributed by argumenting that "they are potentially harmful to children" is in my opinion both prejudiced and narrow. (You don't ban cigarettes, even though many minors get older people to purchase them for them).
I also believe that as an adult I'm entitled to certain rights. If I want to see Joel Schumacher's "Falling Down" where Michael Douglas, fed up with society, goes on a killing spree, I'm free to do this. If I want to write a novel about a guy torturing kittens and enjoying it, I'm free to do so as well. If I want to play a videogame intended for an adult audience, whether it be artsy, pseudo-melancholic, murder riddles or simply good old-fashioned beheading an alien with a chainsaw, shouldn't I be free to do so as well.
Pretty much every government in the world think so (including my own Norwegian government). Maybe you should reconsider too?
Sincerely yours,
Vivendel