It's hard to distill Punk down since at its core it was anti-establishment and anti-conformist, and that could be expressed in various ways. But as others have mentioned, the Dead Kennedys really were the flag bearers for an evolved, purposeful, and thoughtful punk movement you may be looking for. Frontman Jello Biafra famously did not bend to pressure from state and fed on obscenity laws both in court and public debates and is an interesting story on its own.

Their obvious songs being Holiday in Cambodia and Kill the Poor.