Smoking and Drinking Ages - Pointless?

[FallenXxRaven]

First off let's set the scene. I am an "underage" smoker (no flaming me). I know what it does to me and what else it can do. I know as much as any 18+ smoker. So why is it that that I will have to wait until I am 18 to buy cigarettes?
Now, I'm not saying remove the legal smoking age, but lower it to say, 14 or so, the age of most freshmen in high school. By then you know the pros and cons of smoking, so shouldn't you be able to buy your own packs? And it isnt any less harmful to anyone 18+ than it is to any 14 year old.
And the drinking age should be lowered to 18, shouldn't it? I mean at 18 I can go be killed for my country, but God forbid I have a beer. Not only that but by 18 you have learned what alchohol does to your liver, so it is, as with smoking, your choice. And perhaps separate beer from hard liquor? Like 18 for a beer but 21 for any hard stuff. And lets say I'm 18 in a war, after being shot at for a while don't you think it is just fair to let me have a beer?