I'll agree with contacting the command SGTMAJ or CO. Sound advice, that. As for the rest of the post I have to say that it's probably come closer to truly pissing me off than anything I've read on here in a while. Your attitude toward Marines bothers me and stating that you were a Corpsman (there to patch up wounded Marines) while doing so really pushes me over the edge. Not only are you advising another forum member to take violent action against another just to teach him a lesson you're putting all Marines forward as arrogant asses who need to be beaten. Hurt him badly enough to miss duty? Why are you advocating that the OP do something that could land him in jail in the same post that you gave some decent advice about contacting the Marines chain of command?
Why? Because someone that's just a knucklehead punk before boot usually becomes the biggest, most arrogant ***** upon actually becoming a Marine. I've seen it soooo many times. Usually, the only way to fix it is for someone to take them down a notch.
An injury that would make someone miss duty could be a little as a sprained ankle or wrist. Anything that would be just severe enought to put them on Light Duty status for a few days or a week. If he can't do company PT because he instigated a fight out in town and got hurt by a civilian, that will get around his unit. If his Chain of Command knows about it, that will reduce if not eliminate any chance for him wanting revenge, since I'm sure that whoever the OP contacts will see that his story is accurate when he checks and the serviceman has injuries that correspond with the OP's story. The OP will be told that it will not happen again and if he gets any more flack from the servicemember, then to call back immediately and report it.
Besides, I'm sure that his Staff NCO will be ordered to sit on him for awhile and keep him in line. It just won't be worth the trouble for him to seek out retribution.
That's my advise, take it or leave it.
& you can be upset about it if you like. I've been there & done that. I probably have a little different perspective. Besides, any lil' Jarhead acting like that deserves what he has coming. If he's picking fights, he gets what he deserves. I got punked by a corporal in my first FMF unit, I laid him out, & then when I dragged both of our drunken butts into the Regimental Aid Station, the duty Corpsman made me suture the guy's head back up.
We were friends after if not best buddies.
And... a civilian that makes it abundantly clear that he doesn't want to fight & has witnesses to the fact, and then prevents an Active Duty Marine from hurting him but injures him in the process, will not be prosecuted. It's called Self Defense. I trust the law in such situations, especially knowing how civilian courts will look upon a serviceman acting in such a manner. After he's done being prosecuted by the civilian courts, then the military court and his CoC will kick in and the guy will wish he'd never been born.