Lets clarify something here. When the air force asks you if you used drugs or alcohol, they are SPECIFICALLY asking about "ILLEGAL USE OF DRUGS OR ALCOHOL". It is NOT ILLEGAL for you to drink alcohol in mexico if you are 16 or 17 years old. Therefor, you did NOT do anything wrong. Also; in most state; it is totally legal for you to have alcohol in your home, if your parents are being responsible for you and condoning it. Obviously, they can be held accountable and even charged with negligence if they allow you to get plastered. I grew up in an Italian family. Drinking wine with meals was a very common thing. For EVERYONE. Obviously not for breakfast on my way to school. And I ate lunch at school, so that wasn't an issue. But I drank wine with many dinner meals. Probably from about the time I was 10 years old. I won't quote the different state laws, but there is a misconception that even in your own home, with your parents providing it, that it's illegal. Most places it's not. Obviously having friends over and drinking isn't legal because they aren't in THEIR house with their parents. Anyway, that's splitting a fine line. Same thing with drugs. Obviously they mean illegal use of. We've all taken drugs for illnesses that have been prescribed. Therefor that isn't illegal or wrong. This is mostly in reference to alcohol. Drinking in mexico if it's legal, is legal in the eyes of the air force. Drinking wine or a beer in your own home on thanksgiving, or whatever "Your Family" deems as acceptable, is also fine. And for what it's worth, the 21 year old drinking age, is not a Federal Law. The federal government can't make such a law. It's a State law. And each state can be different. At one time, many states were 18 while others were 21. The ONLY reason it seems to be a federal law and every state does it, is because the federal government is guilty of a form of "extortion". Raise your drinking age to 21 years old, or we won't provide you with any highway funds. And I can't tell you how many young enlisted personnel 17-20 years old volunteer to get stationed overseas; partly because they are treated like adults. And yes, an 18 year old can drink at the club on base overseas. Unless of course the base commander sets policy. But it's been about 10 years since I was last stationed overseas. I don't know of any commander that forbid it overseas. Again, it's a state law.
Anyway; there's a difference between illegal and legal use. The military is asking you if you've illegally used drugs and alcohol. Obviously, if a drug wasn't prescribed to you by a doctor, it's pretty much illegal. So definitely fess up to your ALO. As for alcohol, use common sense. Mexico? No, don't mention it. With family at home? (Same with the vineyard story); No, don't mention it. You and a bunch of friends got an older brother/friend/etc... to buy you beer/whiskey and you went out "Partying"? Yes, mention it to your ALO. I think you get the idea.