What are these groups called today? Where are the mini-Renaissances that play a massive role in generating culture? Will these happen less and less as everyone is exposed to the global stream of information?
Look harder, I'd say. See Bar25 in Berlin and the sound that is heard there (Katermukke label, etc.). Or Berghain and it's sound (Ostguton label, etc.). Hell yeah music and "social/political movement" are still as linked as ever. There's still a whole "roots" reggae/dub scene world wide that would besides social/political also come with an embedded spiritual and/or religious movement. Revolutionary hip-hip, like Dead Prez or Immortal, is still strong. In Europe there's still Freetekno. I could go on.
Hell no revolutionary vibes from K. Perry! But it's still there.
> Songs became hits because they gave you a vision you could believe and participate in.
Yes. It's not advertised. They do not hit the charts anymore. So what. Shun the charts. We've got soundcloud, they've got ad-ridden radio and MTV.
I don't think the Clash ever had the kind of mainstream success that someone like Katy Perry has. A more appropriate analogue for "back in the day" would be like Andy Gibb or someone.