I think a lot of the discussion here is boiling down to this statement in particular. Maybe you don't interpret "None of your business" as impolite, but when I

I think a lot of the discussion here is boiling down to this statement in particular. Maybe you don't interpret "None of your business" as impolite, but when I hear it, it's usually a snippy reply to someone being too nosy. It's actually difficult for me to imagine this line being delivered in such a way that I _wouldn't_ interpret as being rude or aggressive.