Music and politics used to be some double act, though their alliances these days are few and far between. Miners, stevedores, farmers and a veritable cacophony of other blue-collar workers have had occasion to channel their message into some of the most powerful songs of the last century. And that's the essence of folk music. Music by, for and about folks. People with stories to tell, injustice to right, and dreams to weave.

Pete Seeger, musicologist, historian, songwriter and agent provocateur, has had a hand in rattling the masses into action while at the same time, shaking lazy preconceptions with his uncanny ear for irony and contradiction. 'Where Have All The Flowers Gone?' must surely be one of the simplest, yet most scathing attacks on the mindlessness of war, immortalised by Marlene Dietrich. 'Guantanamera' saw him bring Cuban poet Josi Marti's plea for racial tolerance to a huge audience; he sang 'Wimoweh' as a tribal chant of hope that found new resonance in apartheid South Africa, while 'Viva La Quince Brigada' celebrated the good fight against the Fascists of Franco's 1930's Spain.

Ever an internationalist, to his core a humanist, Pete Seeger has been a man forever intent on the big picture, always seeking out the universals that can teach us something about one another - so that maybe the same mistakes won't be repeated over and over again.

He carries his 81 years lightly, blithely even. Still playing live shows (he is now frequently accompanied by his bodhran-wielding Nicaraguan grandson, Tao Rodrigruez) and judging by his most recent appearance in Washington DC, still capable of utterly stilling a crowd, he won a Grammy as recently as 1997 for his eponymous CD, Pete. Listening and watching him cast a spell over his audience, you can't help but feel that boy bands and Barbie dolls will come and go, and Seeger will still be plying his very fine trade. He views his unstinting popularity as barely noteworthy; his longevity of minimal interest even in this age when the ephemeral reigns supreme.

"I've never been very much impressed by the changing fashions in music," Seeger avers, "other than something to laugh at. When I was a kid, every month there was a new piece of sheet music on sale in the store, and most of them had ridiculous words like: 'Hello beautiful/how d'you get so beautiful/how d'you get that sunshine in your smile'. On the other hand, some pop songs are extraordinary, and one of these I still sing up and down the Hudson River - we put new words to it, I confess. It's Irving Berlin's 'Blue Skies', a big hit of 1926. But this is the folk process. My father who was a musicologist, said: 'Don't get into big arguments about whether it's folk music or not. These definitions will change every year, but there is a folk process which has been going on in the human race for thousands of years. Cooks change old recipes to fit new stomachs; lawyers change old laws to fit new citizens, and songwriters are always changing old songs to fit new ears'."

In propagating his beliefs about the continuing evolution of folk music, Seeger tells a wonderful tale which he borrowed from Arlo Guthrie, a man equally in thrall of the power of music to mould opinions, broaden minds, and break down barriers:

"I remember Arlo once likened the process of songwriting to being on the bank of a river," Seeger smiles. "He said 'you have to reach out your hand to catch a song as it floats by. And all I know is that I'd hate to live down river from Bob Dylan!"

Pete Seeger still reaches out his hand to catch those songs, though these days they come dropping slow.

"I'm not a prolific songwriter," he notes. "I'm deeply envious of people like Woody Guthrie and Bob Dylan, Malvina Reynolds, Phil Ochs, and others who seem to be able to write a new song every day of the week. I once accused Malvina Reynolds of writing songs before breakfast. She looked at me severely and said: 'You know it's not that simple'."

He's loath to name-check the inheritors of that mantle, believing them well capable of creating their own maps.

"My guess is that of course there are always unusually gifted songwriters in different places at different times," he suggests, "but I don't like to point out any special person. That makes it hard for them; they'll make their way without any encomiums from me. But I do believe that children are often very good songwriters, and many of the best modern songwriters are women. Very often, it was a grandmother in a rocking chair who sang an old song to a granddaughter or grandson, and they remember it years later and carry it on."

Seeger had a long-standing friendship with Woody Guthrie, a man whose influence can be felt across the musical spectrum from Christy Moore to Kelly Joe Phelps, Taj Mahal and Wilco.

"This little short curly-headed guy was an extraordinary creator," Seeger declares. "He had what I call the gift of simplicity. So many of his songs can be translated into any language successfully. I confess when I heard Woody's 'This Land Is Your Land', I thought 'this is too outrageously simple'. Well you know, I said it was one of Woody's lesser efforts! It shows you how wrong you can be! I didn't realise until years later that this song would go from school to school, guitar to guitar, until now it's one of the best known songs in the whole country.

"I never think of Woody without thinking of the corner of his mouth curling up in the beginning of a grin," he says, putting paid to the sometime dour images which have come to be associated with Guthrie. "He was always cracking jokes and kidding people. I remember when he was admitted to hospital (a psychiatric hospital where he eventually died of a hereditary illness called Huntington's Chorea), some friends visited and asked him if he was being treated alright.

"'Oh yeah, they're treating me fine. Besides, this is the freest place in America'. What do you mean? There are bars on the windows. And he answered: Oh no, I m fine here. I can jump up on the table and shout I m a communist and they just say Oh, he s crazy You try doing that any place else in America. See what'll happen!"

Another of Seeger's close acquaintances was one Huddy Ledbetter, a.k.a. Lead Belly, who wrote 'Goodnight Irene' among other songs.

Lead Belly was one of the greatest performers I ever knew, he declares. He didn't write many songs on his own, but he changed every song he sang, adding to it, using a different harmony, etc. He was ambitious. If he hadn't been a musician, he would have been a great athlete. In his 60's his muscles still bulged like iron bands. But he was hit by a terrible disease called Lou Gehrig's Disease. However, he'll go down on history because of his songs, like 'The Bourgeois Blues' which he wrote in Washington after being kicked out of a number of whites-only venues.

Aside from his eclectic circle of artistic acquaintances, Seeger has never shied from manning the barricades. His political nous can at least in part be attributed to the influence of his father. A professor of music at the University of California, he was fired after speaking out against imperialist war during World War 1. Having demonstrated against the detritus of imperialism (segregation, exploitation of manual labourers, etc), does Pete Seeger think we've learned anything from the last 50 years, or are we still fighting the same fight?

"I cannot believe that we haven't learned something: the question is: 'Have we learned enough?'," he asks. "Leaders want to get quick action, and the quick action is usually violent action of some sort, whether it's Kosovo or Iraq or wherever. Only later on it's forced on them that less violent action might have been more useful. I think we've got to find songs and stories to show them. For example, about 10 years ago, when guided missiles were sent from the deck of a warship in the Dead Sea to Afghanistan. This was considered a miracle of technology, to hit pinpoint targets a thousand miles away. But it was one more piece of military stupidity to drop bombs; I think they should have dropped leaflets, not just words, but pictures. Then the local people would find out what their own stupid male leaders are doing, because they're not telling them the truth. Getting the truth heard is difficult: it's like being in a crowded room with everybody talking at once."

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