Cofty,
Sorry, you must be misunderstanding what I've said. I have relatives in Wales and London and the same thing happens when we email, we often misunderstand each others meaning, even though we are speaking the same language.
I wasn't intending to express an opinion of you or suggesting that you should care what I have to say or think nor was I intending to give legal advice. I loved your post and thought your reaction to the situation was spot on. My reply was just a obviously poorly written optional reply that came to mind, of what could have been said when that guy threatened to hit you.
I was thinking at that moment when he threatened to hit you, you could have said to him that if he did indeed hit you, he could be charged with assault and he could end up having to pay a civil fine and pay you for any damages to your face, should there be any. Perhaps a comment like that would make him realize that threatening to hit someone who is simply talking to him in the aisle of a grocery store, could have some serious consequences and it might be prudent of him to think twice about such an over reaction.
Hope that make's more sense (not that it matters)