Attitude.

Punk rock isn’t something you grow out of.  Punk rock is like the Mafia, and once you’re made, you’re made.  Punk rock is not the clothes or the music. Punk rock is an attitude, the "don't-give-me-any-bullshit-'cause-I-can-see-right-through-to-the-heart-of-the situation'-attitude. Because I'm wise to the tricks of the world. We're sick of all the bullshit. Give us some truth.

Joe Strummer