I cannot recall seeing that symbol before today. I guess I’m just too young. (old enough to have children in college) I don’t remember seeing the symbol in college though it’s possible I did without comprehending it. Our oldest children have each studied the Holocaust at various times in their public schooling. Did they study Nazi symbols? I don’t know. I’ll ask them. I’ll start with the one who was studying WWII before Christmas. It seems to me that Nazi symbols were by and large wiped out during my growing up years because no one I knew wanted to be associated with anything that resembled Nazism. It’s semi-understandable that a young sniper squad would have not seen the symbol before. Since there was an investigation with a conclusion that the symbol was used in ignorance, we should let it go and be happy someone noticed and took care of the ignorance.
As long as they are made to understand the nature of the twin lightning bolt symbol in relation to American history and the Marine Corps' own brave contributions to keeping America free from tyranny, I think they will be properly chastened.
I sometimes forget that I am now of an older generation for whom Nazism and its symbols were of far more recent vintage when I was a young man. Those of us who were born in the '40s and '50s knew those symbols implicitly as well as what they represented. When I was a kid and we played war games (with actual toy guns, Heaven forbid!), we often pretended to fight the Germans and Japanese, as our fathers had.
They study military history so everyone in any branch should know about the symbols. Just about anything can be looked up on the internet. No excuse.