What is a senpai?

I was walking to the daily chapel service surrounded by junior high boys in their school uniforms. Usually you can tell the first year students from the second and thirds because of their size. There is one boy in particular who defies that stereotype: he's about 6 feet tall and close to 200 pounds (91 Kg for everyone else in the world!) at the age of 13. I met him during the entrance exam when he was in a group of three boys that cycled in to be interviewed by the panel of teachers that I was on. I remember him because he dwarfed the two other boys by at least a foot (33 cm)!

Anyway, he was walking to chapel service and joking around with his friends by poking them in the ribs. At one point he poked a third year student by mistake. The third year student, apparently a member of the same rugby or touch football club, swirled around to see who had provoked him. The giant first year could have used his size to stand up for what he had done, whether or not is was a mistake. Instead he repeated the phrase, "gomenesai senpai" a few times. It means, "I'm sorry mentor". The 3rd year student had a sense of humor about it and teased him back. But I managed to take a "cultural snapshot" in my mind of something very Japanese.

Thanks to Confucius, Japan and much of Asia for that matter, has great respect for elders. And we're not talking about just wizened wise people. As you can see in this encounter, even a boy two years older commands the respect and deference from a younger though bigger boy. Heck, I think even one year would make a difference. In other encounters in Japanese society, the question, "how old are you" bears more significance than it does in the USA. The questioner wants to know where s/he stands in relation to you. I've heard that people only ask your age if they're interested in becoming friends. So I think that is common in the USA, too. Have you been to Japan and taken a similar "cultural snapshot" to mine? What would a "cultural snapsot" of American values on age look like? Please write me your comments!