So, in your opinion, when is a person old enough to sign a contract, and take an oath? 21? 25? At 17, a young adult can sign and swear, and before their 18th birthday, could possibly be calling air or arty on a position halfway around the world? But in your opinion, they shouldn't be able to have a piece of paper or plastic that allows them to carry a firearm when they are home?But again, that is not a statement of fact, but of opinion.