Don't forget the USMC unifrom traditions as well.

1. The red piping on the dress blues commemorate the original Marines who seized red coats from the English and turned them worng-side out. The inside blue lining made for something of a distinctive look.
2. The high collar of the blues is a remnant of the "leather necks" worn to protect the marines from cutlass slashes.
3. The croix on the officers' covers (a little braided cross that many people never see) is a remnant of the markings used to show the sharp shooters in the rigging who not to shoot at once the enemy was engaged. Kind of a "don't shoot me" sign.
4. The blood stripe on the trousers (Marines don't wear "pants;" they wear "trousers") of NCOs and officers commenorates a battle in Mexico (I think) in which an unusually large number of officers and NCOs were killed.

I could go on with Marine lore, but I'm sure the regiments have many similar tales whether factual or not. It makes for good tales to tell the privates.