When you have private citizens rocking up dressed like this then you probably need to be thinking that things are out of hand regardless of where it is.
But North Carolina is also a Stand Your Ground State:
"A person is justified in the use of deadly force and does not have a duty to retreat in any place he or she has the lawful right to be if either of the following applies:
You reasonably believe that such force is necessary to prevent imminent death or great bodily harm to himself or herself or another; or
You are in your home, vehicle or workplace and that the person against whom the defensive force was used was an unlawful intruder or was attempting to forcibly and unlawfully enter one of the above."
So if they’re on the street or in a park and meet counter protesters these guys can probably fire away and make a robust argument that it was perfectly legal to do so…