Following hard on the explosion of British punk, in 1979 Gang of Four produced post-punk's smartest record, Entertainment! For the first time, a band wedded punk's angry energy to funk's propulsive beats-and used that music to put across lyrics that brought a heady mixture of Marxist theory and situationism to exposing the cultural politics of everyday life.

But for an American college student from the suburbs-and, one expects, for many, many others, including British youth-Jon King's and Andy Gill's mumbled lyrics were often all but unintelligible. Political rock 'n' roll is always something of an oxymoron: rock audiences by and large don't tune in to be lectured to. But what can it mean that a band that made pop songs as political theory actively resisted making that theory legible?

Coming to terms with the impact of Entertainment! requires us to take the mondegreen-the misunderstood lyric-seriously. The old joke has it that the title of R.E.M.'s debut album should have been not Murmur, but Mumble: true, so far as it goes. But that's the title, too, of rock 'n' roll's Greatest Hits compilation-and that strategic inarticulateness itself, which creates such an important role for the listener, has an important politics.