Remember when you'd hear songs like this on Top 40? Now, whether by accident or design (or both), political anthems don't easily spring up among the young because the radio business is so Balkanized and trIvialized. There aren't any commercial stations left that don't cater to a specific demographic, and so universal music is harder to find.
FM underground radio took hold because station owners didn't know what to do with FM stereo bands. Some of them literally gave it away to their kids! (My secret wish is that we someday see a similar revolution with AM stereo bands -- after all, they're just sitting there.)
What part did underground radio play in your life?