Please.Where the play works best is where it challenges the prejudices of its audience. "If at first you don't succeed, redefine success," he says later, and toward the end - in a soundbite that could fall with chilling ease from Donald Rumsfeld's lips - he explains: "I'd rather be alive and ignorant than dead and sensitive to the concerns of the world." Or how about this as a text for his next press conference: "They either love us, or they love to hate us Either way, we're spreading love." Don't laugh. "Victory forgives dishonesty," a commander yells, in a phrase that may well dominate the private thoughts of George Bush. They are certain that their vast technological superiority assures their safety ("Good thing we took the danger out of this war thing, or I'd be worried," a marine laughs) and utterly contemptuous of Arab civilian casualties ("Every man in this country is a lookalike of the Bearded Lady," he later barks).The commentary on the second Gulf war is lacerating. On the hunt for a foreign leader codenamed "the Bearded Lady", four marines set out to perform "the first truly whimsical remote assassination". Last year, Victory at the Dirt Palace ripped the US media to shreds; this year, the group takes on the US military.

In a brutalist style that it has forged over the past four years on the fringe, the cast of four Americans performs less a play, more a dramatised essay. Badham predicts that a new generation of Baader-Meinhof Gangs may be about to rise. If they do, she will provide their most eloquent and dangerous voices. Nicholas Hytner has said that he wants our National Theatre to become politically dangerous again; does he have the courage to stage this writer's work?Another, almost as vibrant, is the Riot Group's Pugilist Specialist. With all political parties in democracies being co-opted by big business and neoliberalism, her characters - and a small but significant portion of the anti-globalisation movement - are tempted by the idea that violent resistance may be the only way forward. I disagree with her politics, but she dramatises the divisions I see and feel every day among left-wingers better than any other writer I know, and she makes a dazzling, terrifying case that has to be answered. In dialogue that feels as though it has been soaked overnight in acid, her characters rip one another's politics apart - and she does not spare the revolutionary-left characters ("I look forward to reading your article in Gulag Today," Maggy's stepson snaps), with whom she most clearly identifies.The fracturing of Maggy's family deftly symbolises the political fracturing of the left: a chasm is opening up once more between reformists and revolutionaries, those of us who think that we can achieve positive change within a political system dominated by America and those who believe that we are kidding ourselves Badham is the poet of that division.

All my life."If it sounds like agitprop, then I'm not doing it justice. Quite apart from telling a cracking story, Badham uses theatre as a forum where political ideas can be clarified, clash and die. "Every interview you've ever given - and who listens to you? They listen if you act It's a political act for a political outcome. Like the IRA, the Sandinistas, the Fretilin and the Burmese Student Army - all the freedom fighters you've always marched behind." Her mother retorts: "Who's been in your head?", only to be told, "You have, Maggy Tanner. Skip the next few paragraphs if you are likely to see the show: it emerges that Maggy's daughter Rebekah is part of a violent anti-globalisation group that is behind the attacks.Badham attacks the cosy centre-left consensus of so many tedious fringe shows from the radical left. "I've watched you my whole life - marching, talking, painting banners, waving placards," Rebekah tells her mother.

The play follows their attempt to come to terms with the trauma (and the resulting repressive legislation) as Maggy's belligerently neoliberal American step-son arrives to visit. A wave of terrorist attacks is hitting London, and Maggy Tanner - a left-wing academic and contributor to the New Statesman - is caught, along with her daughter, in a massive bomb blast on Bond Street. Its companion piece, Capital, is the polar opposite: a violent satire obviously influenced by late-era Harold Pinter, in which a pair of advertising executives are commissioned by the US government to find a way to "spin" a tape obtained by al-Jazeera showing US marines murdering and raping their way through an Iraqi hospital.But it is her third work, Camarilla, that made me feel as if I had been punched in the stomach. Morning on a Rainy Day, the first part of a double bill appearing at C Venue under the title Bedtime for Bastards, is like a pre-September-11 relationship play, but it shows that she can handle character observation and dialogue like a master. But from this sea of predictable, knee-jerk tedium, two stunning (and very different) new voices have risen.My favourite by far is the extraordinary 27-year-old Australian playwright Van Badham She has three wildly differing shows on the fringe. One more routine about how Americans are all obese imbeciles, and I think my head might have burst; one more person howling at some smugly inactive audience that "children are dying, children are dying", and I might have lapsed into a coma.