In Ronin, when Robert De Niro's character is trying 'interrogating' Sean Bean's character, he mispronounces the place name 'Hereford'*.
In the film he constantly says 'Hear-ford' as opposed to the proper pronounciation of 'Hair-Re-Ford'.
I can see two explanations:
Out of universe: It's just the 'normal' American mis-pronounciation of UK place names. However, I'd have thought Robert De Niro would have known better and certainly Sean Bean (being English) would know how to pronounce it.
In universe: It just proves that Robert De Niro's character is purely messing with Sean Bean's character as he doesn't know how to pronounce Hereford either, which he would if he'd visited and/or trained there.
So, which is it? Or, is it something else? Is there any secured information if this was part of Robert De Niro's character's plan of calling out Sean Bean's character as an impostor?
*Note - Hereford is where the SAS are based in south-west England.