Lower the consumption, possession and sale of alcohol age to 18

Isn't it time we lowered the consumption, possession and sales of alcohol to age 18 or 19 the LEAST? Over the years the government claims 21 is the appropriate age to drink alcohol because the mind is fully matured and more responsible by then rather than an 18 year old. At the age of 18 we can sacrifice our lives for this country of "freedom" and, move out on our own, work, raise kids, vote and many other things EXCEPT buy, possess or consume alcohol. Isn't that a bit extreme? We the people of America should decide whether lowering the drinking age to 18 or 19 is a good idea or not...NOT the government. As an end result, lowering the alcohol laws would greatly teach 18+ adults about how to drink responsibly rather than at 21 when they go crazy and end up in a bad position.