I've always wondered about the offense value behind the term "yank". Being British, I've never used it myself.
To my recollection there's an American team named "the yankies". Not that the team associates it self with the word, but if there's any American folk who still use this board, what are your thoughts on it?
"Stop looking at the walls, look out the window." ~ Karl Pilkington On Art
I think it would just depend on how someone said it to me. I've never really spent any time around British people before, but I have watched (by American standards, at least) a lot of British film and TV. I've seen characters use the term Yank in a casual, offhand way to refer to Americans, and it didn't bother me in the slightest. I've also seen characters use it in a clearly derogatory and hateful way, that would make me want to slap the piss out of them.
Like with all things, it's all about context and intent.