"which you, nonetheless, see nothing disrespectful about..."

You're misunderstanding. I have said, and as Allan has pointed out I don't use the word (except once in a private joke to good and valued American friends, who did not take offence) in deference to any Americans, in case it's disrespectful. Suffice to say however, that many on these isles would never know they were insulting someone if they used the word and so perhaps those who are offended by such a minor faux pas could have the good grace and dignity to accept a cultural difference as being just that and move on, or "You've just got to put yourself in their position, let go of the ego, and empathize".

Cripes, I wish I'd never weighed in now. Perhaps we'll enjoy a pint one day and you'll get too meet this egotistical, misunderstanding ignoramus.

"there are many comic aspects in inter-cultural communication."

This thread is one of them ;-) (or is it a tragedy?)

"Likewise we British are in ignorance over some things."

This is very true. For instance, no-one has yet explained what a "beaner" is.