Local Beers should be served to 18 years old kids. After all if they’re fighting and dying for us in Afghanistan and Iraq, then why can’t they have a fracking beer?
When I joined the Air Force in 1987, the military had changed its policy (not sure if it was a law, regulation, policy) on drinking on base. Essentially, it used to be if you were on base, and in the service (not somebody's kid) you could drink. When I joined, that had changed to the base having to abide by local law.
Most of the old-timers who were there basically took the attitude of you can drink, but don't get the unit into trouble. They were pretty good. They usually asked someone to keep an eye on us younguns to make sure we made it back to the barracks without hassle from the Security Police (MPs where I was, since my first training assignment was on an Army base).
I know I was able to when I was 18 and in the Army.