Why do people say this is a USA forum?

To some degree it is from ignorance. Too many assume that because it is in their language that it is their forum. I see so many questions that don't give details because they think all the people reading it are from their town. The entire English speaking world is here and it's not always easy to tell where the writer is from.

It's not a US-only site.

Yahoo! IS an American corporation (headquartered in California) but it operates worldwide. Yahoo! Answers has portals in many countries. The English-language Y!A sites (US, UK, Canada, Australia, and several others) are linked and share a common pool of questions and answers. Questions and answers posted on any of those sites will appear on ALL of them.

It would only be a USA forum in that Yahoo is a USA Company and the majority of users are in the USA.

i have been here since 2006 and not once have I seen that being claimed. I have, however, seen that insulting others and chatting @ other users in addl details is a violation of the guidelines.

I suppose because home office being in Sunnyvale, CA, USA and it is owned in the USA- which makes it a USA site, unless you must argue semantics. how does it matter????

because americuh owns teh worldd, dontcha know?

it's not a US only site, but the main site is primarily english speaking though there are offshoots for other countries