There is move afoot to lower the drinking age from 21 back to 18. I was born in 1967, and thus was always on the window of not being allowed to drink in college at Georgia Tech while my few month older friends always could. As a consequence or nevertheless (well correlation is not causation, so perhaps I should say: in addition), I imbibe not.
Yet the logic for this drinking age always escaped me. The problem it is claimed is that driving and drinking do not mix, neither shaken nor stirred. The solution is obvious, drinking without driving does not kill innocents (generally), driving without drinking still does kill innocents. Let us raise the driving age.
Driving age is more easily regulated (you can't realistically ask an older friend to buy a car for you) and raising it will save more lives, and perhaps discourage binge drinking.
Driving is a privilege, and should be treated as such. Some will claim they need cars to get to work or wherever. This may be true for some, given how they have chosen to arrange their lives, yet somehow almost everyone survived without a private car 100 years ago. There is public transport, bicycles, carpooling, taxis, etc. available. I am very dubious about the whole concept of "I need ..." as opposed to "it would be convenient if I ..."
What is the optimal age for driving? I do not know, I would find it improbable the optimal age is 16 (though I did get my own license on my 16th birthday). Given safety rates, it might be as old as 25 for men, though there need to be rational trade-offs between value of time and value of life. Experiments in various states would be interesting to analyze as empirical evidence could help clarify the issue.
An article on the current debate is here:
Opening a Debate Over a Lower Drinking Age