A friend of mine was a Navy MD and went to Nam. He later told me about how he was operating on wounded marines and army soldiers in a MASH type of a situation, when Charlies started to slip into the camp and began firing and throwing grenades.
The wounded Marines who were not under anesthesia got their weapons and hobbled out or crawled out of the OR tent and the little recovery tent. Then, they took care of the Charlies and came back for their surgery or back to the recovery tent.
My friend was amazed. The young marines were concerned about his safety, his nurses and corpmen, and they did not feel that they did anything special. They were just being Marines and doing what had to be done.