Common, just smile and offer a fresh bird!
This happens often, you can't get into an escalating conflict with anyone in a car firstly. Secondly your size is not a factor at all, unless you're a current street fighter and just got into a scrap yesterday. Besides you don't know what your adversary might pull oout from the car, in again - a quickly escalating conflict.
I know it is easier said than done, I've had quite a background myself, but I want to be alive for my kids, so how many guys I can take on, blah, blah is irrelevant. One day you take on too much and it is over - just like that. Best to indicate in some non-threatening manner that you disapprove of the behavior and let things go.
Key is - must stay alive, must enjoy the ride!
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