On the day Gordon Brown made his "major policy speech" on Afghanistan, repeating his surreal claim that if the British army did not fight Pashtun tribesmen over there, they would be over here, the stench of burnt flesh hung over the banks of the Kunduz River. Nato fighter planes had blown the poorest of the poor to bits. They were Afghan villagers who had rushed to siphon off fuel from two stalled tankers. Many were children with water buckets and cooking pots. "At least" 90 were killed, although Nato prefers not to count its civilian enemy. "It was a scene from hell," said Mohammed Daud, a witness. "Hands, legs and body parts were scattered everywhere." No parade for them along a Wiltshire high street.

I saw something similar in south-east Asia. An incendiary bomb had razed most of a thatched village, and bits of charred people were hanging on upended fishing nets. Those intact lay splayed and black, like large spiders.

I have never believed you need witness such a hell to comprehend the crime. A standard-issue conscience is enough for all but the morally corrupt and powerful. Fresh from another dysfunctional photo opportunity with troops in Afghanistan - a contrivance far from the impoverished suffering of that country - Brown "authorised" the Rambo-style rescue of Stephen Farrell, a journalist of British and Irish nationality, at the site of the Nato attack. It was a stunt that went wrong. A British soldier was killed and Farrell's guide, Sultan Munadi, an Afghan journalist, was abandoned and killed. Munadi's family now fully appreciates the different worth of British and Afghan lives.

During the 1914-18 slaughter, Prime Minister Lloyd George confided: "If people really knew [the truth], the war would be stopped tomorrow. But of course they don't know and can't know." Have we not yet advanced over a century's corpses to a point where the likes of Brown are denied their mendacious subterfuge? The Afghan war is a fraud. It began as an American vendetta for domestic consumption in the wake of the 11 September 2001 attacks, in which not a single Afghan was involved. The Taliban, who are Afghans, had no quarrel with the United States and were dealing secretly with the Clinton administration over a strategic pipeline. They offered to apprehend Osama Bin Laden and hand him over to a clerical court, but this was rejected.

The establishment of a permanent US/Nato presence in a resource-rich, strategic region is the principal reason for the war. The British are there because that is what Washington wants. Preventing the Taliban from storming our streets is reminiscent of President Lyndon B Johnson's plaint: "We have to stop the communists over there [Vietnam] or we'll soon be fighting them in California."

There is one difference. By refusing to bring the troops home, Brown is likely to provoke an atrocity by young British Muslims who view the war as a western crusade; the recent Old Bailey trail made that clear. He has been told as much by British intelligence and security services. Brown's own security adviser has said as much publicly. As with Tony Blair and the bombs of 7 July 2005, he will bear ultimate responsibility for bringing violence and grief to his own people.

More than MPs' fake expenses, it is this corrupting and trivialising of life and death that mark a fitting end to the "modernised" Labour Party, the party of criminal war. Do the delegates preparing for the party's annual rituals in Brighton comprehend this? It says enough that most Labour MPs never demanded a vote on Blair's bloodshed in Iraq and gave him a standing ovation when he departed. One timid motion proposed by the "grass roots" at Brighton might be allowed. This concludes that "a majority of the public believe that the war [in Afghanistan] is unwinnable". There is no suggestion that it is wrong, immoral and based on lies similar to those that led to the extinction of a million Iraqis, "an episode more deadly than the Rwandan genocide", according to one scholarly estimate.

This is largely why the game of parliamentary politics is over for so many Britons, especially the young. In 2005, a bent system allowed Blair to win with fewer popular votes than the Tories in their catastrophe of 1997. New Labour's greatest achievement is the lowest turnouts since universal voting began. Today, voters watch Brown give billions of public money to casino banks while demanding nothing in return, having once hailed their practices as an inspiration "for the whole economy". At the recent meeting of G20 leaders in London, Brown distinguished himself by opposing, and killing, a modest Franco-German proposal for a limit on bonuses and penalties for companies that broke it. The gap between rich and poor in Britain is now the widest since 1968.

New Labour's causes and effect extend from the one in five young people denied employment, education and hope to the £12m that Blair coins in a year, "advising" the rich and lecturing to them at £157,000 a time. For Blair's and Brown's more extreme mentors and courtiers, such as the twice-disgraced Peter Mandelson, this represents the most sought-after achievement of all: the positioning of Labour to the right of the Tories, though it is probably correct to say the two main parties have converged, competing feverishly with each other to threaten cuts in public services in order to pay for the bailing out of the banks and for the drug lords of Kabul. There is no mention of cutting the billions to be spent on replacing Trident nuclear submarines designed for the defunct cold war.

The game is over. Corporatism and a reinvigorated militarism have finally appropriated parliamentary democracy, a historic shift. For those Afghan villagers blown to pieces in our name, one craven motion at Labour's conference is too late. At the very least, the party's "grass roots" might ask themselves why.