No Drinking Age

Recently it has been in the news that some groups are pushing to lower the drinking age in the U.S. from 21 to 18. There are two sets of arguments, for it: One by some college association about students going wild in their senior year or something and one by the people that say military people should be able to drink.
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I have a better idea. I say there should not be a drinking age at all. Now don't get your britches in a bunch, let me finish. I say regardless of age, you can drink once you get a high school diploma. No diploma, no drinking, even when you reach 50 or 75. I would grandfather the law, though. I would have it apply to anyone born after 30 years prior to the year the law is passed. That would give all those 20-somethings some incentive to go get that GED. I imagine the high school drop-out rate would become miniscule. That also covers all military personnel, because you have to have a high school diploma to join the military.
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Your driver's license or photo I.D. (if you don't drive) would simply be stamped "GRAD." Non-grad drinkers and servers/suppliers to non-grad drinkers would be subject to the same laws that are currently in place for underage drinkers/servers. And what about the geniuses that graduate at 12 or 16? Well, they can legally drink, but since they are still minors, I imagine their parents would have to sign a permission waiver or something. Besides, if they are so smart, I doubt they would be abusing alcohol anyway. And if being able to drink gives kids the incentive to work hard in high school, that's good right? I think so.

Congratulations! Now go have a beer!