Martin had no reason to believe this guy was going to go away.
Remember, Zimmerman never once told Martin why he was there ~
Cold rain, dark of night, strange Hispanic man following him closely in a pickup truck ~ ............. I think Martin had every reason to be fearful.
A reasonable man would think he was being set up for a robbery.
Anyone find Martin's cellphone yet? Last time anyone had anything about the cellphone is that the police property report for Martin did not report a cellphone. It did report the Skittles!
As witnessed, a guy walking away from you is no threat.
Also as witnessed, a guy sitting on your chest beating you IS a threat.
You lose again.