You can hear the wringing of hands and tearing of cloth all the way down Farringdon Road. Dismayed by the local election results, convinced that Labour will be crushed in Thursday's byelection, afraid that this will presage disaster in the next general election, my fellow columnists are predicting the end of the civilised world. But I can't understand why we should care.

Yes, I worry about what the Tories might do if they get in. I also worry about what Labour might do if it wins another term. Why should anyone on the left seek the re-election of the most rightwing government Britain has had since the second world war?

New Labour's apologists keep reminding us of the redistributive policies it has introduced: Sure Start children's centres, reductions in child poverty, raising the school leaving age, the national minimum wage, flexible hours for parents and carers, better conditions for part-time workers, the decent homes programme, free museums, more foreign aid. All these are real achievements and deserve to be celebrated. But the catalogue of failures, backsliding and outright destruction is much longer and more consequential.

One fact alone should disqualify this government from office: we have a cabinet of war criminals. The Nuremberg tribunal characterised a war of aggression as "the supreme international crime". It is not just that Britain's Labour government launched and sustained an unprovoked war, it also sabotaged all means of achieving a peaceful resolution. In April 2002 it helped the Bush administration to sack José Bustani, the head of the Organisation for the Prohibition of Chemical Weapons, in order to prevent him settling the dispute over Iraq's alleged weapons of mass destruction. In two separate offers before the invasion, Saddam Hussein agreed to meet the terms the US and Britain were demanding. But they slapped him down and concealed his offers from their electorates. (All references are on my website.)

Cluster bombs can be legally used because the British government helped to block an international ban in 2006: it is still holding out against an outright ban at the current talks in Dublin. The government has undermined another international peace agreement - the nuclear non-proliferation treaty - by deciding to renew the Trident missile programme. It was the first administration to announce a policy of pre-emptive nuclear attack: even the great nuclear enthusiast Harold Macmillan never went this far. In 2007 the defence secretary, without parliamentary debate, revealed that the US would be allowed to use the listening station at Menwith Hill for its missile defence system.

Labour appears to be prepared to meet any demand the Bush administration makes, however outrageous. In 2003 the government signed a one-sided extradition treaty, permitting the US to extract our citizens without producing prima facie evidence of an offence. In the same year the defence secretary announced that he would restructure the British armed forces to make them "inter-operable" with those of the United States, ensuring for the first time in British history that they became functionally subordinate to those of another sovereign power.

Labour's foreign policy is as unethical as Margaret Thatcher's. It provides military aid to the government of Colombia, whose troops are involved in a campaign of terror against the civilian population. It granted an open licence for weapons exports to the government of Uzbekistan, and sacked the British ambassador when he tried to draw attention to the regime's human rights abuses. It has collaborated with the US programme of extra-judicial kidnapping and imprisonment, left our citizens to languish in Guantánamo Bay, and made use of Pakistani torture chambers in seeking to extract testimony from British suspects. Until 2005 it tied its foreign aid programme to the privatisation of public utilities in some of the world's poorest countries. Last year it held out against reform of the International Monetary Fund's unfair allocation of votes.

The proportion of the British population in prison has risen by a fifth since the Tories left office. Today Britain locks up 151 out of every 100,000 people. The Chinese judiciary, by contrast, which is notorious for its willingness to bang up anyone and everyone, jails 119 people per 100,000; Burma imprisons 120; Saudi Arabia 132. The Serious Organised Crime and Police Act, passed in 2005, contains clauses that permit the police to ban any demonstration, however peaceful. It is one of a long series of bills the Labour government has passed that restrict the right to protest.

The citizen has been re-regulated; business has been deregulated. Last year deaths caused by serious injuries at work rose by 11%: a predictable result of the sacking of 1,000 staff at the Health & Safety Executive and a 24% reduction in workplace inspections. In 2006 the government instructed the Serious Fraud Office to drop its corruption case against the arms manufacturer BAE Systems. It has obstructed efforts by other states to investigate the company.

Labour has shifted taxation from the rich to the poor, cutting corporation tax from 33% to 28% and capital gains tax from 40% to 18%, and introducing a new entrepreneurs' relief scheme, taxing the first million of capital gains at just 10%. It tried to raise the income tax paid by the poorest earners from 10% to 20%. Labour has lifted the inheritance tax threshold from £300,000 to £700,000, and maintained the cap on the highest rates of council tax. While vigorously prosecuting benefits cheats, it has allowed tax avoidance, mostly by the very rich, to reach an estimated £41bn. Inequality today is slightly worse than it was when Labour took power in 1997 (the Gini coefficient which measures it has risen from 0.33 to 0.35).

Both as chancellor and prime minister, Gordon Brown has forced the private finance initiative into almost all public services. His privatisation schemes have crept into places where the Conservative government never dared to tread. Labour has waged war against our planning system and overseen a disastrous decline in social housing: under Thatcher an average of 46,600 social homes were built every year; under Tony Blair the average was 17,300. Labour is closing post offices, small schools and GPs' surgeries, while overseeing a doubling of airport capacity and the construction of 4,000km of trunk roads. These developments ensure that even the modest targets in the climate change bill are likely to be missed. Carbon dioxide pollution fell faster under the Conservatives than under Labour.

Above all, the Labour government has destroyed hope. It has put into practice Thatcher's dictum that "there is no alternative" to a market fundamentalism that subordinates human welfare to the demands of business. Labour has created a political monoculture that kills voters' enthusiasm, and has delayed electoral reforms that would have given smaller parties an opportunity to be heard. All we are left with is fear: the fear that this awful government might be replaced by something slightly worse. Fear has destroyed the Labour party, but people keep supporting it in trepidation of letting the other side win.

Save this government? I would sooner give money to the Malarial Mosquito Conservation Project. Of all the causes leftist thinkers might support, New Labour must be the least deserving.

monbiot.com