Isn't it funny how differently Japanese and American games approach protagonists? The typical western videogame protagonist is in his late 20's, early 30's. He's often a little "too old for this shit", and is either, or was, a member of some armed force, be it military or mercenary.
The Japanese protagonist is a teenager, usually under the age of 18. He's inexperienced, and is often thrust into action, usually by some calamity, often the destruction of a home town or the disappearance of some family member. Despite his youth, he will still exhibit extraordinary combat proficiency.