The Argus: Brighton Festival Thumb When it came to an authority to speak on the creation and impact of protest songs, there couldn't have been a better guest than Billy Bragg.

Although the show was ostensibly a talk about music journalist Dorian Lynskey's new authoritative tome 33 Revolutions Per Minute - tracing the history of the protest song from Billie Holliday's Strange Fruit to Green Day's American Idiot - the talk turned into an examination of the impact of punk and the miners' strike, both on the music scene of the 1980s and 1990s and Bragg's own career.

This focus allowed the speakers to go into much more depth on the knotty questions of whether a protest song can be truly effective, the pitfalls of political songwriting which allowed Ronald Reagan to use Bruce Springsteen's Born In The USA as a campaign song, and whether many political performers are simply preaching to the converted.

Bragg was an engaging speaker, mixing self-deprecation ("I learned the pitfalls of political songs by walking into them like an iron bar") with examples of performers and songs who changed his life, from Joe Strummer and the tragic Phil Ochs to folk-singing miner Jock Purdon.

Lynskey was slightly overshadowed by Bragg's big personality but injected some memorably pithy comments, not least some of his most hated protest songs including Michael Jackson's Earth Song and The Cranberries's Zombie.

Meanwhile host Luke Bainbridge, co-founder of the Observer Music Monthly, played a perfect role, asking insightful questions and ensuring both guests got a chance to speak, while at the same time not trying to force his own opinions on the audience.