A person is old enough at 18 years old to go fight a war and possibly die in it. So I believe they are also old enough to drink a beer if they chose to. The legal drinking age of 21 is a type of prohibition against a select group of adults who can do anything else adults are permitted to do. Except consume alcohol. I found this article very interesting. But that is probably because it supported the view on the subject I already had.
http://www.dailylush.com/archives/co...nking_age.html