Outside Kabul, Afghanistan is bleaker, its provinces more inaccessible and lawless, than it was under the Taliban. If anyone leaves town, they do so in convoys. Afghanistan is a place where it is easy for people to disappear and perilous for anyone to investigate their fate. Even a seasoned aid agency such as Médécins Sans Frontières was forced to quit after five staff members were murdered last June. Only the 17,000-strong US forces, with their all-terrain Humvees and Apache attack helicopters, have the run of the land, and they have used the haze of fear and uncertainty that has engulfed the country to advance a draconian phase in the war against terror. Afghanistan has become the new Guantánamo Bay.

Washington likes to hold up Afghanistan as an exemplar of how a rogue regime can be replaced by democracy. Meanwhile, human-rights activists and Afghan politicians have accused the US military of placing Afghanistan at the hub of a global system of detention centres where prisoners are held incommunicado and allegedly subjected to torture. The secrecy surrounding them prevents any real independent investigation of the allegations. "The detention system in Afghanistan exists entirely outside international norms, but it is only part of a far larger and more sinister jail network that we are only now beginning to understand," Michael Posner, director of the US legal watchdog Human Rights First, told us.

When we landed in Kabul, Afghanistan was blue with a bruising cold. We were heading for the former al-Qaida strongholds in the south-east that were rumoured to be the focus of the new US network. How should we prepare, we asked local UN staff. "Don't go," they said. None the less, we were able to find a driver, a Pashtun translator and a boxful of clementines, and set off on a five-and-a-half-hour trip south through the snow to Gardez, a market town dominated by two rapidly expanding US military bases.

There we met Dr Rafiullah Bidar, regional director of the Afghan Independent Human Rights Commission, established in 2003 with funding from the US Congress to investigate abuses committed by local warlords and to ensure that women's and children's rights were protected. He was delighted to see foreigners in town. At his office in central Gardez, Bidar showed us a wall of files. "All I do nowadays is chart complaints against the US military," he said. "Many thousands of people have been rounded up and detained by them. Those who have been freed say that they were held alongside foreign detainees who've been brought to this country to be processed. No one is charged. No one is identified. No international monitors are allowed into the US jails." He pulled out a handful of files: "People who have been arrested say they've been brutalised - the tactics used are beyond belief." The jails are closed to outside observers, making it impossible to test the truth of the claims.

Last November, a man from Gardez died of hypothermia in a US military jail. When his family were called to collect the body, they were given a $100 note for the taxi ride and no explanation. In scores more cases, people have simply disappeared.

Prisoner transports crisscross the country between a proliferating network of detention facilities. In addition to the camps in Gardez, there are thought to be US holding facilities in the cities of Khost, Asadabad and Jalalabad, as well as an official US detention centre in Kandahar, where the tough regime has been nicknamed "Camp Slappy" by former prisoners. There are 20 more facilities in outlying US compounds and fire bases that complement a major "collection centre" at Bagram air force base. The CIA has one facility at Bagram and another, known as the "Salt Pit", in an abandoned brick factory north of Kabul. More than 1,500 prisoners from Afghanistan and many other countries are thought to be held in such jails, although no one knows for sure because the US military declines to comment.

Anyone who has got in the way of the prison transports has been met with brutal force. Bidar directed us to a small Shia neighbourhood on the edge of town where a multiple killing was still under investigation. Inside a frozen courtyard, a former policeman, Said Sardar, 25, was sat beside his crutches. On May 1 2004, he was manning a checkpoint when a car careened through. "Inside were men dressed like Arabs, but they were western men," he said. "They had prisoners in the car." Sardar fired a warning shot for the car to stop. "The western men returned fire and within minutes two US attack helicopters hovered above us. They fired three rockets at the police station. One screamed past me. I saw its fiery tail and blacked out."

He was taken to Bagram, where US military doctors had to amputate his leg. Afterwards, he said, "an American woman appeared. She said the US was sorry. It was a mistake. The men in the car were Special Forces or CIA on a mission. She gave me $500." Sardar showed us into another room in his compound where a circle of children stared glumly at us; their fathers, all policemen, were killed in the same incident. "Five dead. Four in hospital. To protect covert US prisoner transports," he says. Later, US helicopters were deployed in two similar incidents that left nine dead.

In his builders' merchant's shop, Mohammed Timouri describes how he lost his son. "Ismail was a part-time taxi driver, waiting to go to college," he says, handing us a photograph of a beardless, short-haired 19-year-old held aloft in a coffin at his funeral last March. "A convoy delivering prisoners from a facility in Jalalabad to one in Kabul became snarled up in traffic. A US soldier jumped down and lifted a woman out of the way. She screamed. Ismail stepped forward to explain she was a conservative person, wearing a burka. The soldier dropped the woman and shot Ismail in front of a crowd of 20 people."

Mohammed received a letter from the Afghan police: "We apologise to you," the police chief wrote. "An innocent was killed by Americans." The US army declined to comment on Ismail's death or on a second fatal shooting by another prison transport at the same crossroads later that month. It also refused to comment on an incident outside Kabul when a prison patrol reportedly cleared a crowd of children by throwing a grenade into their midst. However, we have since heard that the CIA's inspector general is investigating at least eight serious incidents, including two deaths in custody, following complaints by agents about the activities of their military colleagues.

There are insurgents active in the Gardez area, as there are throughout the south of Afghanistan, remnants of the old order and the newly disaffected. Every morning it takes Afghan police several hours to pick along the highway unearthing explosives concealed overnight. And so it was mid-morning before we were able to leave town, crawling over the Gardez-Khost pass, some 10,000ft high. No one saw us slipping on to the fertile Khost plain, where Osama bin Laden once had his training camps - the camps were destroyed by US cruise missiles in August 1998. Today a shrine to Taliban loyalists still greets travellers to the city, although no one here would say they preferred the old life.

US Camp Salerno, the largest base outside Kabul, dominates the area around Khost. Inside the city, Kamal Sadat, a local stringer for BBC World Service, told how he was detained last September and found himself locked up in a prison filled with suspects from many countries. "Even though I showed my press accreditation, I was hooded, driven to Salerno and then flown to another US base. I had no idea where I was or why I had been detained." He was held in a small wooden cell, and soldiers combed through his notebooks, copying down names and phone numbers. "Every time I was moved within the base, I was hooded again. Every prisoner has to maintain absolute silence. I could hear helicopters whirring above me. Prisoners were arriving and leaving all the time. There were also cells beneath me, under the ground." After three days, Sadat was flown back to Khost and freed without explanation. "It was only later I learned that I had been held in Bagram. If the BBC had not intervened, I fear I would not have got out." After his release, the US military said it had all been a misunderstanding, and apologised.

Camp Salerno, which houses the 1,200 troops of US Combined Taskforce Thunder, was being expanded when we arrived. Army tents were being replaced with concrete dormitories. The detention facility, concealed behind a perimeter of opaque green webbing, was being modernised and enlarged. Ensconced in a Soviet-era staff building was the camp's commanding officer, Colonel Gary Cheeks. He listened calmly as we asked about the allegations of torture, deaths and disappearances at US detention facilities including Salerno. We read to him from a complaint made by a UN official in Kabul that accused the US military of using "cowboy-like excessive force". He eased forward in his chair: "There have been some tragic accidents for which we have apologised. Some people have been paid compensation."

We put to him the specific case of Mohammed Khan, from a village near the Pakistan border, who died in custody at Camp Salerno: his relatives say his body showed signs of torture. "You could go on for ages with a 'he said, she said'. You have to take my word for it," said Cheeks. He remembered Khan's death: "He was bitten by a snake and died in his cell." He added, "We are building new holding cells here to make life better for detainees. We are systematising our prison programme across the country."

For what reason? "So all guards and interrogators behave by the same code of behaviour," the colonel said. Is it not the case that an ever-increasing number of prisoners have vanished, while others are being shuttled between jails to keep their families in the dark? Cheeks moved towards his office door: "There are many things that are distorted. No one has vanished here ... Look, the war against the Taliban is one small part. I want the Afghan people with us. They are the key to ending conflict. If they fear us or we do wrong by them, then we have lost."

However, many Afghans who celebrated the fall of the Taliban have long lost faith in the US military. In Kabul, Nader Nadery, of the Human Rights Commission, told us, "Afghanistan is being transformed into an enormous US jail. What we have here is a military strategy that has spawned serious human rights abuses, a system of which Afghanistan is but one part." In the past 18 months, the commission has logged more than 800 allegations of human rights abuses committed by US troops.

The Afghan government privately shares Nadery's fears. One minister, who asked not to be named, said, "Washington holds Afghanistan up to the world as a nascent democracy and yet the US military has deliberately kept us down, using our country to host a prison system that seems to be administered arbitrarily, indiscriminately and without accountability."

What has been glimpsed in Afghanistan is a radical plan to replace Guantánamo Bay. When that detention centre was set up in January 2002, it was essentially an offshore gulag - beyond the reach of the US constitution and even the Geneva conventions. That all changed in July 2004. The US supreme court ruled that the federal court in Washington had jurisdiction to hear a case that would decide if the Cuban detentions were in violation of the US constitution, its laws or treaties. The military commissions, which had been intended to dispense justice to the prisoners, were in disarray, too. No prosecution cases had been prepared and no defence cases would be readily offered as the US National Association of Criminal Defence Lawyers had described the commissions as unethical, a decision backed by a federal judge who ruled in January that they were "illegal". Guantánamo was suddenly bogged down in domestic lawsuits. It had lost its practicality. So a global prison network built up over the previous three years, beyond the reach of American and European judicial process, immediately began to pick up the slack. The process became explicit last week when the Pentagon announced that half of the 540 or so inmates at Guantánamo are to be transferred to prisons in Afghanistan and Saudi Arabia.

Since September 11 2001, one of the US's chief strategies in its "war on terror" has been to imprison anyone considered a suspect on whatever grounds. To that end it commandeered foreign jails, built cellblocks at US military bases and established covert CIA facilities that can be located almost anywhere, from an apartment block to a shipping container. The network has no visible infrastructure - no prison rolls, visitor rosters, staff lists or complaints procedures. Terror suspects are being processed in Afghanistan and in dozens of facilities in Pakistan, Uzbekistan, Jordan, Egypt, Thailand, Malaysia, Indonesia and the British island of Diego Garcia in the southern Indian Ocean. Those detained are held incommunicado, without charge or trial, and frequently shuttled between jails in covert air transports, giving rise to the recently coined US military expression "ghost detainees".

Most of the countries hosting these invisible prisons are already partners in the US coalition. Others, notably Syria, are pragmatic associates, which work privately alongside the CIA and US Special Forces, despite bellicose public statements from President Bush (he has condemned Syria for harbouring terrorism, for aiding the remnants of the Saddam Hussein regime, and most recently has demanded that Syrian troops quit Lebanon).

All the host countries are renowned for their poor human rights records, enabling interrogators (US soldiers, contractors and their local partners) to operate. We have obtained prisoner letters, declassified FBI files, legal depositions, witness statements and testimony from US and UK officials, which document the alleged methods deployed in Afghanistan - shackles, hoods, electrocution, whips, mock executions, sexual humiliation and starvation - and suggest they are practised across the network. Sir Nigel Rodley, a former UN special rapporteur on torture, said, "The more hidden detention practices there are, the more likely that all legal and moral constraints on official behaviour will be removed."

The only "ghost detainees" to have been identified by Washington are a handful of high-profile al-Qaida operatives such as Abu Zubayda, Bin Laden's lieutenant, who vanished after being picked up by Pakistani authorities in Faisalabad in March 2002. In June of that year, US defence secretary Donald Rumsfeld said Zubayda was "under US control". He did not say where, although sources in the Pakistani government said Zubayda was being held at a CIA facility in their country.

In May 2003, Bush clarified the fate of Waleed Muhammad bin Attash, an alleged conspirator in the USS Cole bombing, who disappeared after being arrested by police in Pakistan in April 2003. Bush described Attash as "a killer ... one less person that people who love freedom have to worry about"; he is also one more person who has never appeared on a US prison roll.

In June 2004, a senior counterterrorism official in Britain confirmed that Hambali (a nom de guerre) - accused of organising the October 2002 Bali bombings and unseen since Thai police seized him in August 2003 - was "singing like a bird", apparently at the US base on Diego Garcia.

Evidence we have collected, however, shows that many more of those swept up in the network have few provable connections to any outlawed organisation; experts in the field describe their value in the war against terror as "negligible". Former prisoners claim they were released only after naming names, coerced into making false confessions that led to the arrests of more people unconnected to terrorism, in a system of justice that owes more to Stanley Milgram's Six Degrees Of Separation - where anyone can be linked to everyone else in the world in as many stages - than to analytical jurisprudence.

The floating population of "ghost detainees", according to US and UK military officials, now exceeds 10,000.

The roots of the prison network can be traced to the legal wrangles that began as soon as the first terror suspects were rounded up just weeks after the September 11 attacks. As CIA agents and US forces began to capture suspected al-Qaida fighters in the war in Afghanistan, Alberto Gonzales, White House counsel, looked for ways to "dispense justice swiftly, close to where our forces may be fighting, without years of pre-trial proceedings or post-trial appeals".

On November 13 2001, George Bush signed an order to establish military commissions to try "enemy belligerents" who commit war crimes. At such a commission, a foreign war criminal would have no choice over his defence counsel, no right to know the evidence against him, no way of obtaining any evidence in his favour and no right of attorney-client confidentiality. Defending the commissions, Gonzales (now promoted to US attorney general) insisted, "The suggestion that [they] will afford only sham justice like that dispensed in dictatorial nations is an insult to our military justice system."

When the first prisoners arrived at Guantánamo Bay in January 2002, Donald Rumsfeld announced that they were all Taliban or al-Qaida fighters, and as such were designated "unlawful combatants". The US administration argued that al-Qaida and the Taliban were not the official army of Afghanistan, but a criminal force that did not wear uniforms, could not be distinguished from civilians and practised war crimes; on this basis, the administration claimed, it was entitled to sidestep the Geneva conventions and normal legal constraints.

From there, it was only a small moral step for the Bush administration to overlook the use of torture by regimes previously condemned by the US state department, so long as they, too, signed up to the war against terror. "Egypt, Jordan, Malaysia, Thailand, Indonesia, Pakistan, Uzbekistan and even Syria were all asked to make their detention facilities and expert interrogators available to the US," one former counterterrorism agent told us.

In the UK, a similar process began unfolding. In December 2001, the then home secretary David Blunkett withdrew Britain from its obligation under the European human rights treaty not to detain anyone without trial; on December 18, the Anti-terrorism, Crime and Security Act was passed, extending the government's powers of arrest and detention. Within 24 hours, 10 men were seized in dawn raids on their homes and taken to Belmarsh and Woodhill prisons (some of them will have been among those released in the past week).

Subsequently the Foreign Office subtly modified internal guidance to diplomats, enabling them to use intelligence obtained through torture. A letter from the Foreign & Commonwealth Office directorate sent to Sir Michael Jay, head of the diplomatic service, and Mathew Kidd of Whitehall liaison, a euphemism for MI6, suggested in March 2003 that although such intelligence was inadmissible as evidence in a UK court, it could still be received and acted upon by the British government. The government's attitude was spelt out to the Intelligence and Security Committee of MPs and peers by foreign secretary Jack Straw who, while acknowledging that torture was "completely unacceptable" and that information obtained under torture is more likely to be embellished, concluded, "you cannot ignore it if the price of ignoring it is 3,000 people dead" [a reference to the September 11 attacks].

One former ambassador told us, "This was new ground for the FCO. As long as we didn't do it, we're OK. But by taking advantage of this intelligence, we're encouraging the use of torture and, in my opinion, are in contravention of the UN Convention Against Torture. What worried me most was that information obtained under torture, given credence by some gung-ho Whitehall warrior, could be used to keep another poor soul locked up without trial or charge."

Although the true extent of the US extra-legal network is only now becoming apparent, people began to disappear as early as 2001 when the US asked its allies in Europe and the Middle East to examine their refugee communities in search of possible terror cells, such as that run by Mohammed Atta in Hamburg which had planned and executed the September 11 attacks. Among the first to vanish was Ahmed Agiza, an Egyptian asylum seeker who had been living in Sweden with his wife and children for three years. Hanan, Agiza's wife, told us how on December 18 2001 her husband failed to return home from his language class.

"The phone rang at 5pm. It was Ahmed. He said he'd been arrested and then the line went dead. The next day our lawyer told me that Ahmed was being sent back to Egypt. It would be better if he was dead." Agiza and his family had fled Egypt in 1991, after years of persecution, and in absentia he had been sentenced to life imprisonment by a military court. Hanan said, "I called my mother-in-law in Egypt. Finally, in April, she was allowed to see Ahmed in Mazrah Torah prison, in Cairo, when he revealed what had happened."

On December 18 2001, Agiza and a second Egyptian refugee, Mohammed Al-Zery, had been arrested by Swedish intelligence acting upon a request from the US. They were driven, shackled and blindfolded, to Stockholm's Bromma airport, where they were cuffed and cut from their clothes. Suppositories were inserted into both men's anuses, they were wrapped in plastic nappies, dressed in jumpsuits and handed over to an American aircrew who flew them out of Sweden on a private executive jet.

Agiza and Al-Zery landed in Cairo at 3am the next morning and were taken to the state security investigation office, where they were held in solitary confinement in underground cells. Mohammed Zarai, former director of the Cairo-based Human Rights Centre for the Assistance of Prisoners, told us that Agiza was repeatedly electrocuted, hung upside down, whipped with an electrical flex and hospitalised after being made to lick his cell floor clean. Hanan, who was granted asylum in Sweden in 2004, said, "I can't sleep at night without expecting someone to knock on the door and send us away on a plane to a place that scares me more than anything else. What can Ahmed do?" Her husband is still incarcerated in Cairo, while Al-Zery is under house arrest there. There have been calls for an international independent investigation into the roles of the Swedish, US and Egyptian authorities.

We were able to chart the toing and froing of the private executive jet used at Bromma partly through the observations of plane-spotters posted on the web and partly through a senior source in the Pakistan Inter Services Intelligence agency (ISI). It was a Gulfstream V Turbo, tailfin number N379P; its flight plans always began at an airstrip in Smithfield, North Carolina, and ended in some of the world's hot spots. It was owned by Premier Executive Transport Services, incorporated in Delaware, a brass plaque company with nonexistent directors, hired by American agents to revive an old CIA tactic from the 1970s, when agency men had kidnapped South American criminals and flown them back to their own countries to face trial so that justice could be rendered. Now "rendering" was being used by the Bush administration to evade justice.

Robert Baer, a CIA case officer in the Middle East until 1997, told us how it works. "We pick up a suspect or we arrange for one of our partner countries to do it. Then the suspect is placed on civilian transport to a third country where, let's make no bones about it, they use torture. If you want a good interrogation, you send someone to Jordan. If you want them to be killed, you send them to Egypt or Syria. Either way, the US cannot be blamed as it is not doing the heavy work."

The Agiza and Al-Zery cases were not the first in which the Gulfstream was used. On October 23 2001, at 2.40am at Karachi airport, it picked up Jamil Qasim Saeed Mohammed, a Yemeni microbiologist who had been arrested by Pakistan's ISI and was wanted in connection with the USS Cole attack. On January 10 2002, the jet was used again, taking off from Halim airport in Jakarta with a hooded and shackled Mohammed Saeed Iqbal Madni on board, an Egyptian accused of being an accomplice of British shoe bomber Richard Reid. Madni was flown to Cairo where, according to the Human Rights Centre for the Assistance of Prisoners, he died during interrogation.

Since then, the jet has been used at least 72 times, including a flight in June 2002 when it landed in Morocco to pick up German national Mohammed Zamar, who was "rendered" to Syria, his country of origin, before disappearing.

It was in December 2001 that the US began to commandeer foreign jails so that its own interrogators could work on prisoners within them. Among the first were Haripur and Kohat, no-frills prisons in the lawless North West Frontier Province of Pakistan which now hold nearly as many detainees as Guantánamo. In January, we attempted to visit Kohat jail, but as we drove towards the security perimeter our vehicle was turned back by ISI agents and we were escorted back to the nearby city of Peshawar. We eventually located several former detainees, including Mohammed, a university student who described how he was arrested and then initially interrogated in one of many covert ISI holding centres that are being jointly run with the CIA. Mohammed said, "I was questioned for four weeks in a windowless room by plain-clothed US agents. I didn't know if it was day or night. They said they could make me disappear." One day he was bundled into a vehicle. "I arrived in Kohat jail. There were 100 prisoners from all over the Middle East. Later I was moved to Haripur where there were even more."

Adil, another detainee who was held for three years in Haripur after illegally crossing into Pakistan from Afghanistan, where he had escaped from the Taliban, says, "US interrogators came and went as they pleased." Both Mohammed and Adil said they were often taken from the hot cell and doused with ice-cold water. Adil says, "American women ordered us to get undressed. They'd touch us and taunt us. They made us lie naked on top of each other and simulate acts."

Mohammed and Adil were released without charge in November 2004 but, according to legal depositions, there are still 400 prisoners detained in the jails at the request of the US. Among them are many who it is extremely unlikely took part in the Afghan war: they are too young or too old to have been combatants. Some have taken legal action against the Pakistani authorities for breach of human rights.

A military intelligence official in Washington told us that no one in the US administration seemed concerned about the impact of the coercive tactics practised by the growing global network on the quality of intelligence obtained, although there was plenty of evidence it was unreliable. On September 26 2002, Maher Arar, a 34-year-old Canadian computer scientist, was arrested at New York's JFK airport as a result of a paper-thin evidential chain. Syrian-born Arar told us, "I was pulled aside by US immigration at 2pm. I told them I had a connecting flight to Montreal where I had a job interview." However, Arar was "rendered" in a private jet, via Washington, Portland and Rome, landing in Amman, Jordan, where he was held at what a Jordanian source described as a US-run interrogation centre. From there, he was handed over to Syria, the country he had left as a 17-year-old boy. He says he spent the next 12 months being tortured and in solitary confinement, unaware that someone he barely knew had named him as a terrorist.

The chain of events that led to Arar's arrest, or kidnapping, began in November 2001, when another Canadian, Ahmad Abou El-Maati, from Montreal, was arrested at Damascus airport. He was accused of being a terrorist and asked to identify his al-Qaida connections. By the time he'd endured two years of torture, El-Maati had reeled off the names of everyone he knew in Montreal, including Abdullah Almalki, an electrical engineer. Almalki was arrested as he flew into Damascus airport to join his parents on holiday in May 2002, and would spend the next two years being tortured in a Syrian detention facility.

Almalki knew Arward Al-Bousha, also from Ottawa, who in July 2002, upon arriving in Damascus to visit his dying father, was also arrested. El-Maati, Almalki and Al-Bousha all knew Maher Arar by sight through Muslim community events in Ottawa. After his release from jail in Syria, uncharged, in January 2004, El-Maati admitted that he had erroneously named Maher Arar as a terrorist to "stop the vicious torture". Arar, who was eventually released in October 2003 after a Syrian court threw out a coerced confession in which he said he had been trained by al-Qaida, told us, "I am not a terrorist. I don't know anyone who is. But the tolerant Muslim community I come from here in Canada has become vitriolic and demoralised." Arar's case is now the subject of a judicial inquiry in Canada, but since his release and that of Al-Bousha and Almalki, another five men from Ottawa have been detained in Syria, Egypt and Saudi Arabia.

Five days after the US supreme court ruled in July 2004 that federal courts had jurisdiction over Guantánamo, Naeem Noor Khan, a 25-year-old computer programmer from Karachi, disappeared during a business trip to Lahore. He was not taken to Guantánamo. His father Hayat told us that he learned of his son's fate after a neighbour called on August 2 to say that US newspapers were running a story about "the capture of a figure from al-Qaida in Pakistan" who had led "the CIA to a rich lode of information". An unnamed US intelligence official claimed Naeem Noor Khan operated websites and email addresses for al-Qaida. The following day Pakistan's information minister trumpeted the ISI's seizure of Naeem Noor Khan on behalf of the US on July 13. The prisoner had "confessed to receiving 25 days of military training from an al-Qaida camp in June 1998". No corroborative evidence was offered.

Babar Awan, one of Pakistan's leading advocates, representing the family, said he had learned from a contact in the Pakistani government that Naeem Noor Khan was wanted by the US, having been named by one of a group of Malaysian students who had been detained incommunicado and threatened with torture in Pakistan in September 2003. Awan said, "The student was subsequently freed uncharged and described how he was threatened until he offered the names of anyone he had met in Pakistan. There is no evidence against Naeem Noor Khan except for this coerced statement, and even worse he has now vanished and so there is no prison to petition for his release."

Khan had been swallowed up by a catch-all system that gathers up anyone connected by even a thread to terror. Unable to distinguish its friends from its enemies, the US suspects both.

Dawn broke on the festival of Eid and four US army vehicles gunned their engines in preparation for a "hearts and minds" operation in Khost city, Afghanistan. A roll call of marines, each with their blood group scrawled on their boots, was ticked off and we were added to the muster. The convoy hurtled towards the city. Men and boys began to run alongside. First a handful and then a dozen. The crowd was heading for a vast prayer ground, and soon there were thousands of devotees in brand newEid caps and starched shalwas marching out to pray. The US Humvees pulled over. The armoured personnel carriers, too. A dozen US marines stepped down, eyes obscured by goggles, faces by balaclavas.

They fell into formation and stomped into the crowd while a group of Afghan police looked on incredulously. "Keep tight. Keep tight. Keep looking all around us," a US marines captain shouted. More than 10,000 Pashtun men were now on their knees praying as a line of khaki pushed between them.

An egg flew. Then another. "One more, sir, and the guy who did it is going down," a young sergeant mumbled, as the disturbed crowd rose to its feet. Bearded men with Kalashnikovs emerged from behind a stone wall and edged towards us, cutting off our path. The line of khaki began to panic, and jostled the children. "Back away, back away now," shouted the sergeant. Suddenly an armoured personnel carrier roared to meet us. "Jump up, people," the captain shouted, and the convoy sped back to Camp Salerno.

And perhaps this event above all others - of a nervous phalanx of US marines forcing its way across a prayer ground on one of the holiest, most joyous days in the Islamic calendar, an itching trigger away from a Somalian-style dogfight of their own making - is the one that encapsulates everything that has gone wrong with the global war against terror. The US army came to Afghanistan as liberators and now are feared as governors, judges and jailers. How many US marines know what James Madison, an architect of the US constitution, wrote in 1788? Reflecting on the War of Independence in which Americans were arbitrarily arrested and detained without trial by British forces, Madison concluded that the "accumulation of all powers, legislative, executive and judiciary, in the same hands may justly be pronounced the very definition of tyranny"


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Afghanistan