Well the same can be said for hip hop and it's attitude towards crime, drugs (Many punk bands lead straight edge lifestyles) the police...
It's easy to isolate parts of every genre but looking at the genre of punk in general you see many left wing band with anti-war messages and also many straight edge acts who promote not using drugs or drinking
That's perfectly correct, but most of those punks i know, and i have many as friends, they aren't punks because they are left wing or against war or capitalism, they are punks, because they dont care about anything, drink, and let themselves down, and those sorts of punks i dont give ANY respect.