If your are interesting in broadning your musical taste into classical and symphonic music, I have an endless list of suggestions. For policial classical music, I think none is better than my personal favorite composer Dimitri Shostakovitch, who wrote many symphonies, song cycles and operas about the political system in the former Soviet Union. Generally, the Russian (or Soviet) 20th century composers often have political messages more or less concealed in their works.
Another suggestion is to look into rock/pop music from the 60's and 70's. If you like punk, you should look into the British and American 70's bands, they held a similar status in music as the hiphop did during the 80's. Try bands like Dead Kennedy's, Iggy and the Stooges, New York Dolls, Sex pistols, The Damned, The Clash, 999, Generation X. Or from the 70's glamrock era that overlap with the punk and new wave, Venus in furs, Brian Eno, Velvet underground, Marc Bolan.
Late Beatles, Jimi Hendrix, The Who, Queen, David Bowie, Kraftverk is also interesting, it's rock classics that have had a major impact on all popular music.
If you like hiphop, you might like the old skool from the 80's, when the genre was new. Grandmaster Flash, Melle Mel, Africa Bambataa...I still think songs like "The message" and "World destruction" are absolutely great - and it's good dance music as well.
Just to name a few
For world music, I just adore the traditional Tibetan singing that sounds like contemporary composer Lygeti (he made the music for the movie 2001 - not the intro from the opera Also sprach Zarathustra and the An die schonen Vienna walz when the planets line up, of course )
