Next Friday marks the 10th anniversary of the start of the US war in Afghanistan. This event is unlikely to be celebrated in America with the same brio that accompanied the anniversary of September 11, which filled the newspapers with tragic and inspiring stories of the victims of that day.
Anyone who has followed the conflict from the beginning - as I did as a reporter in northern Afghanistan in the autumn of 2001 - cannot fail to be astounded at how long it has lasted. At the start it seemed as if the "war on terror" was never going to get anywhere. The ragtag army of the Northern Alliance looked incapable of driving its broken tanks as far as Kabul, let alone overthrowing the Taliban government.
When the B-52 bombers first appeared high in the sky, they seemed too tiny to overturn the balance of power against the Taliban. But as you approached the front line, things changed. What looked from afar like pretty puffs of smoke rocked the earth as if the end of the world were at hand. Not surprisingly the Taliban retreated south, slipping away overnight.
Did they flee for their lives in the face of a superior enemy, or was the plan to regroup in the mountains for a classic guerrilla campaign to retake the capital? We do not know.
What we do know is that one of the Taliban's most battle-hardened fighters, Jalaluddin Haqqani, quickly established himself in North Waziristan, in the tribal areas of Pakistan along the border with Afghanistan. Within months he started a new jihad against the American forces.
The Haqqani network is now at the centre of a damaging row between Pakistan and the US. Admiral Mike Mullen, the outgoing chairman of the US joint chiefs of staff, said last week that the Haqqanis had planned and conducted the September 14 attack on the US embassy in Kabul with the support of Pakistan intelligence. The network was "a veritable arm" of Pakistan's Inter-Service Intelligence (ISI), Adm Mullen said.
Such a blunt accusation is a clear indication of the strain that the US military is under. A presidential election is coming up and a timetable for withdrawal by 2014 has been set in motion, but the government of President Hamid Karzai is incompetent, corrupt and incapable of standing on its own.
Since Adm Mullen's comments, US administration officials have been rowing back, saying there is no clear proof of ISI complicity in the attack, while the secretary of state, Hillary Clinton, has stressed the need for both countries to find a way to preserve their alliance.
On one level, this looks like a typical game of good cop, bad cop, but the reality is more complex. It is now US policy to try to engage the Taliban in talks ahead of the withdrawal. For the US military, the Haqqani network may be the most dangerous terrorists, the group which helped Osama bin Laden to settle in Afghanistan and introduced suicide bombing. But they are also seen as a possible conduit for talks with the Taliban leadership.
During the 1980s, Jalaluddin Haqqani was the favoured anti-communist mujahid of the CIA and Pakistani intelligence. He received thousands of US dollars and got to try out the new US weaponry first. His attacks on the Soviet airbase at Khost, just over the border from Pakistan, were a tour highlight of visiting journalists and officials.
A late recruit to the Taliban, he has always been seen as his own man. He was offered a post in Mr Karzai's first cabinet, but preferred to fight instead. Clearly Jalaluddin Haqqani is Afghanistan's man for all seasons.
The key issue is to what extent the ISI controls the network. There is no doubt that the ISI had close links with him in the 1980s. And he would have been unlikely to have been able to move so quickly onto the offensive after 2001 without ISI help.
But we should be wary of jumping to conclusions. It is likely that ISI, while nurturing the Haqqani network as a proxy force, exerts less direct control than in the past. The network has become a power in North and South Waziristan, settling feuds and brokering alliances.
The Haqqanis are seen as the "good Taliban", in contrast to the bulk of the local Pakistani Taliban, the TTP, who oppose the Pakistani state and carry out attacks on domestic soil. The Haqqani network is too powerful to control, but also too important for the ISI to leave to its own devices.
General Pervez Musharraf, the former military leader who is preparing to return to politics, has come closest to explaining to the outside world why Pakistan is not going the fight the Haqqanis. Speaking to The Daily Telegraph in London, Gen Musharraf said the Americans had to understand Pakistan's national interest, which was to prevent Afghanistan from becoming dominated by India.
With the US talking of withdrawing in 2014, Pakistan had to "fend for itself against all the exterior pressures, all the exterior manoeuvrings and political manoeuvrings against Pakistan". In a word, the Haqqanis are an insurance policy.
Washington will not be reassured to hear its supposed ally justify support of an organisation that has just mounted a sophisticated and well-planned attack on the US embassy.
Looking back on those 10 years, from the "defeat" of the Taliban to the resurgence of the Haqqanis, the conclusion has to be that things are never as simple as they seem to the blundering foreigner.
The best epitaph of this war may have been written by Rory Stewart, a Briton (now an MP) who walked the length of Afghanistan in 2002 and then spent years trying to persuade everyone who would listen that sending more troops was not the answer. He has just co-authored a book, Can Intervention Work?, on the perils of state building by outsiders.
He concludes: "The foreigners who comprise 'the international community' are usually much weaker than they imagine. They are inevitably isolated from local society, ignorant of local culture and context, and prey to misleading abstract theories."