"Ballad of the Green Berets" was a Vietnam War era song, IIRC. Certainly I can remember it being played on the radio, and I wasn't around during WWII.

The drunken quarrelling, I have heard, was generally between soldiers and sailors when they met in taverns. Groups of one branch of service would band together, regardless of nationality, to battle their multinational foes of the other service. Then the Military Police would come, beat on everybody, haul them off, and the fun would be over for the night.