What makes a great protest song?

The phrase "protest song" is problematic. Many artists have seen it as a box in which they might find themselves trapped. Barry McGuire, who sang the genre-defining 1965 hit Eve of Destruction, protested: "It's not exactly a protest song. It's merely a song about current events." Bob Dylan told his audience, shortly before performing Blowin' in the Wind for the first time: "This here ain't a protest song." There are good reasons why the term is regarded with suspicion. Protest songs are rendered a disservice as much by undiscerning fans as by their harshest critics. While detractors dismiss all examples as didactic, crass or plain boring, enthusiasts are prone to acting as if virtuous intent suspends the usual standards of musical quality, when any music lover knows that people make bad records for the right reasons and good records for the wrong ones. It makes sense to treat protest songs first and foremost as pop music. Many are artistically brilliant, because pop thrives on contradiction and tension. Electricity crackles across the gap between ambition and achievement, sound and meaning, intention and reception. So the best protest songs are not dead artefacts, pinned to a particular place and time, but living conundrums. The inevitable difficulty of contorting a serious message to meet the demands of entertainment is the grit that makes the pearl. In songs such as Strange Fruit, Ohio, A Change Is Gonna Come or Ghost Town, the political content is not an obstacle to greatness, but the source of it. They open a door and the world outside rushes in. Extracted from 33 Revolutions Per Minute by Dorian Lynskey, published by Faber & Faber Ltd on 3 March at £17.99. To order a copy for £13.59 with free UK p&p go to theguardian.com/bookshop or call 0330 333 6846