Few wars have had as extensive coverage as the Vietnam war. This documentary, released three decades after the event, follows a peaceful march in 1971 by Vietnam War Vets against the continuation of the war.

Grainy, black-and-white footage of interviews with, and actions by, Vietnam veterans' as they march to protest at the symbolically important Lexington Green (where the American Revolution started) is set to the elegaic music of Gorecki's Symphony Of Sorrowful Songs.

The piece begins by reminding us of the atrocities and injustice of the war, much of it through interviews with the vets. One, in his early Twenties, describes how as an interrogator he witnessed a prisoner having his insides cut out and being left to die. The idea was to persuade a second prisoner to talk. In the end, both were killed.

The interviewer asks: "How do you know he's a VC?" The vet replies: "The general reply would be, 'Because he's dead.'" Many of those interogated were old women and children ("They were unlucky").

There is a grim litany of atrocities: images of napalm burns, torture, mutilation and appalling genetic deformities caused by the defoliant Agent Orange, used on a massive scale by the US in its vain attempt to gain supremacy in the Vietnam jungle. But it is really the vets' eloquence, the feeling of senselessness, disgust and the need to make amends that really strikes home.

"Guilt just eats you away. I feel like a war criminal - I've got to absolve myself somehow before I die," says one.

The archive footage alone is powerful stuff.

Interweaved with the vets' testimonies and footage of their protests is a discussion by contemporary commentators on the nature and history of dissent and civil disobedience. This doesn't sit altogether comfortably with the rest of the composition.

The lamentful soundtrack sets the tone for a contemplative piece. The commentary aims to put the vets' march into historical perspective and asks us to step back and consider the importance of civil disobedience today. But, disappointingly, Bestor Cram and Mike Majoros fail to make any real connections with parallel injustices and actions today. The danger is that this propagates the idea that civil disobedience is a concept that academics are wheeled on to talk about or something that happened 30 years ago.