When a thug ass Blood is gangbanging, he often sports a red bandana to alert fellow American citizens of his "Thug Nature" and his affiliation to bloods, esp. LA Pirus. IF you where blue around these folks, they will blow your head off.
Stupid White Boy- "Oh shit that person is wearing a red bandana, he must be a thug."
Another white boy wearing all blue: "Nah they are just posers"
(Gunshot and white boy wearing blue is killed)