I see what you are saying, but I think here it is a hostile act, whereas there it is also symbolic. I don't know a ton about the Middle-eastern culture, but I think shoes are very symbolic. From what I understand, if you show the bottom of your foot to someone, it is a direct insult (so you have to be careful when crossing your legs). If you show the bottom of your shoe to someone it means that you feel they are beneth you. I imagine if you fling that shoe at them, it is much worse.
I have to say, I don't like GW very much, but the man has MOVES!
Warmest wishes!
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