Art and politics are a tricky pair. Guernica works. Nicholson Baker's Checkpoint doesn't. As a rule, politics tends to dumb down art.

In popular music the rule is slightly relaxed for obvious reasons. Protest songs are the best example of how politics and art can work, but only if the politics isn't party politics, but rather, the politics of morality. (They're not the same thing, in case you were wondering.) Can you imagine What's Going On bogged down with political strategy and Tricky Dick references? ((Four dead in) Ohio may be the exception to the exception.)

Effective protest songs have the power of persuasion. Ineffective protest songs (Steve Earl's last album for example) polarize and end up preaching only to the converted.

Which brings me to the Dixie Chicks. They don't make overtly political music although they do sometimes touch on moral issues in their songs. But Natalie Maines' raw political comments on a London stage a few years ago estranged them from their mostly conservative audience, taking away their power to persuade.

That's too bad because their latest album is a killer set of songs. I've been listening to it for a few days now and I can't get over the depth of the material; one great song after another, ending with a masterpiece of moral protest, I Hope.

It's too bad, too, that Maines didn't deliver her remarks in London with the same eloquence and tone that she does in that song. Those "happy ever afters" that she sings about could have been shared all around.