Legal majority age is one of those things...
And I'm a firm believer that it needs to be consistent across the board.
If a 16 year old in the Military is old enough to deal with the emotional consequenses of killing people during deployment then he/she is old enough to vote, drink alcoholic beverages, be financially responsible for children sired, and use tobacco products.
But if not...then we need to figure out a more reasonable age and be consistent across the board.
All of these "privileges" and responsibilities that we grant to those of legal are inconsistent at the moment. And different around the world.
We could use a more cohesive formula than what we currently are....some of this is a "states rights" issue. Some is not.