It is easier to repeat an old lie than reveal a new truth. Politicians of both main parties have their mouths bandaged by their own guilt. To change tactics now is to admit to failures of policy that have resulted in the deaths of 212 courageous soldiers.
When parliament resumes in mid-October, the PM will read out the names of the 24 soldiers that have been killed since mid-July. By then, there may be 40 names. Public opinion is increasingly rejecting the notion that British lives should be lost for a corrupt Karzai regime and a rigged election.
Vietnam veteran and US Senator John Kerry asked at the end of the Vietnam war in 1971. "How do you ask a man to be last one to die for a mistake?" British politicians should be haunted by the same nightmare.
Our incursion into Helmand province in 2006 was a grave error. Then, only seven soldiers had died – five in accidents. Our soldiers have paid the price of Helmand with the loss of another 204 lives. It is time for politicians to admit that our war aims are impossible.
The sooner a peace strategy is devised the better. Some gains made by the Nato presence can be protected. If we delay, outraged public opinion may demand a panic withdrawal as damaging as America's exit from Saigon. US politicians said then what our UK politicians are saying now: "We cannot afford to lose." The fear back then was the domino effect. If Vietnam went communist, so would all other countries in South East Asia. It was a lie, of course. Now we are told that terrorism in Britain is held back because of our war in Afghanistan. That's a lie, too. If it was true we should have plans to start new wars in Pakistan, Somalia and the Yemen.
Now we're told soldiers must keep on dying – perhaps for another 40 years – for which of the following causes?
*To guarantee the re-election of a corrupt president and his family.
*To allow the depraved thieves of the Afghan police to rule the villages.
*To continue the abject failure of the policy to eradicate drugs that have flooded the world with cheap heroin.
*To strengthen the oppressive, medieval warlords
*To defend barbaric human rights practices.
*Or because no politician will admit that it was stupid to stir up the hornets' nest of Helmand.
I asked David Miliband in July if he had ever talked to the Taliban. He said he had not. Neither have our generals. When people are killing our soldiers, it is important to ask them why.
Would their answer be: (a) we are killing them so that when the last British soldier dies we can go and plant bombs in Birmingham, or (b) we are killing them because they are Ferengi infidels in our country; it is our sacred duty in this Jihad to drive them from our country.
Answer (a) is the preposterous fiction that the Government and opposition peddle. All wars end in deals and the insurgents almost always win against an alien invader. The Taliban will stay and we will go. But it's easier to repeat an old lie than reveal a new truth.
Politicians are in denial, and refuse to confront the deep futility of the war in Afghanistan. It is more comfortable to tilt at the windmills of peripheral issues. Last year, European countries were howled at for dodging their share of the burden. Now, it is the myth that more troops and helicopters are solutions.
The key issues are ugly truths on Karzai's corruption, evil human rights record and the atrocities of his police and army. Politicians blaming foreigners or each other are on comfortable ground. It is easier than thinking.
British lives are being lost to keep Karzai as president. His record on human rights includes his refusal to pardon a young man sentenced to 20 years in prison for accessing an internet article on women's rights, while pardoning a group of young men guilty of gang-raping a 13-year-old girl. After all, boys will be boys. A suspended Afghan woman MP and human rights' prizewinner Malalai Joya said that the rights of women in Afghanistan now are worse than under the Taliban.
Of the $25bn aid poured into Afghanistan, only 20 per cent reached its intended recipients. The increase in the number of new Afghan millionaires and billionaires in Kabul include members of President Karzai's family. Meanwhile, poverty is deepening among other Afghanis. After eight years of generous Western aid, Afghanistan has the world's third highest child mortality rate and the world's second highest maternity mortality rate.
In 2001 an ebullient member of the Russian Duma thumped me on the back and gave me his mock congratulations. "You Brits are very clever. You have captured Afghanistan. We Russians did that – in six days. We were there for 10 years. We spent billions of rubles, killed a million Afghanis, and lost 15,000 of our soldiers. When we ran out, there were 300,00 Mujahadin in the hills around Kabul. It will happen to you."
Nato's Afghan war is in its final stages. Talks are already taking place with the Taliban. Military operations should be confined to our defended compounds. Patrols on foot and in vehicles should cease. They serve no purpose and expose our troops as targets for the Taliban roadside bombs.
A month ago the answer was "more helicopters". In the space of 10 days, the British Army has destroyed two of our £40m Chinooks. They were slightly damaged, but reparable. We could not guard them until a heavy lift helicopter could take them to a safe compound. When an Army is in such a perilous situation, it is time to withdraw to safe havens.
President Obama has a practical approach. He has appointed a new Nato supremo who has used the previously forbidden words of "exit" and "defeat". We should dump the illusion of victory and devise a peace exit strategy. It could consolidate the few gains made and avoid the bloodbath of the panic retreat of the Americans from Saigon. Public opinion will not tolerate indefinitely the pointless slaughter of our soldiers. We cannot win hearts and minds with bombs, bullets and bacabazi.
Clinging to myths is a deadly distraction. Afghans say: "Truth is like the sun. When it rises it is impossible to hide it." It will be some time before truth dawns in our parliament.
The author is Labour MP for Newport West