If you can’t handle yourself in a fist fight, don’t get into one. HE upped the anti and shot an unarmed man.
The punk was armed with size and fists
Martin was 7" taller than Zimmerman, and according to the only official report, he was attacked by Martin, and was being severely beaten; since neither of us were there, I'll go with the police report.
In your example, don't attack with your fists, and then whine when you get shot.
A man without a gun, that started the physical attack is not a victim, and I wouldn't hesitate to defend myself with a gun under those conditions.