Once the ANA were regarded as just a component of the Afghan solution, an essential cornerstone within a restructured Afghan state. In the years following 2002 it was thought that they could enable Nato forces to defeat the Taliban. By late 2009, however, deciding that the insurgency had become too entrenched to crush militarily, Britain and America began exploring ways of reconciling the Taliban leadership, hoping that the ANA could enforce a political solution to the war.

Yet the premise that the Taliban's senior leadership ever wanted to join a political process now seems deeply questionable. Early efforts to open dialogue with them were plagued by setbacks. Then in September last year, Professor Burhannuddin Rabbani, head of the US-funded High Peace Council set up by President Karzai to conduct reconciliation talks, was killed when a suicide bomber posing as a Taliban peace envoy detonated a device hidden in his turban.

More than any other incident, Rabbani's murder pole-axed hopes for an overall political settlement, dispersing the rewards of the surge in Helmand and other provinces into detached, solitary orbits. One senior Nato officer told me that the killing had left the reconciliation initiative "overwhelmed by gloom", and admitted that there was increasing doubt among Western missions that the Taliban even wanted to negotiate. The assassination was neither denounced nor denied by the Taliban's ruling Quetta Shurah. Despite immediate accusations of Pakistani complicity, little is known of the true identity of Rabbani's killer, nor of the real masterminds behind the attack. Whoever was ultimately responsible, Rabbani's assassination resulted in major policy shifts which derailed direct talks with the Taliban, exacerbated tensions between Afghanistan's rival ethnic groups, and hardened the stand-off with Pakistan.

So, rather than being the military arm of a political solution, the ANA has instead become the sole heir to an open-ended conflict. On its forces' shoulders will rest the future of their country: a heavy demand to be placed on a young army with a large, predatory neighbour like Pakistan. 

Najibullah's forces found themselves in a similar position between 1986 and 1992. After taking office, the president made several peace overtures to the mujahideen as part of an all-encompassing national policy that offered an amnesty to every insurgent who accepted the principles of reconciliation. Insurgents were promised seats in the government; Islam was recognised as having a pivotal role in a series of proposed constitutional reforms; the country's judicial system was offered up to the control of the mullahs. Yet each reconciliation attempt failed, rejected by both the insurgents and by Pakistan, which wanted greater influence in Afghanistan than that on offer. In the absence of an alternative plan, Najibullah's army fought on until the withdrawal of Russian funding and supplies caused its eventual collapse.

There are limits to these comparisons. The loathing of the Russians was far more widespread in Afghanistan than is antipathy towards Nato, irreparably damaging the future of Najibullah and communism in the country. Karzai may be despised in some quarters, and appears to have little ideology beyond survival, yet the imperfect form of proto-democracy in Afghanistan today still attracts Afghans more than anything the Taliban can offer. Moreover, the Taliban are militarily much weaker than the mujahideen who fought Najibullah. Despite limited Pakistani and Saudi financial support they have no patron comparable to  the US and its international allies who funded and armed the Afghan resistance throughout the 1980s.

Cynics would do well to remember too that the majority of Afghans, Pashtuns, Tajiks and Hazaras do not want the Taliban back. Nor should Nato. The Taliban were by their nature a regional threat and their emirate was the perfect host to global jihadists. Despite some limited PR tinkering, not much seems to have changed. The Taliban's regard for dialogue and political process was exemplified by the way Rabbani was killed. They are not fighting a jihad for a power share in a democratic government. Rather than resurrect the failed template of dialogue, foreign diplomats would do better to recognise the implacable essence of their enemy.

Even Boris Gromov, who could be forgiven for a sense of schadenfreude at seeing his old foes suffer in Afghanistan as his troops did, nevertheless urged Nato to keep its nerve in Afghanistan. "We are utterly dissatisfied with the mood of capitulation at Nato headquarters," he co-wrote in the New York Times in 2010, "be it under the cover of ‘humanistic pacifism' or pragmatism. We insist that Nato troops stay in the country until the necessary conditions are provided to establish stable local authorities capable of independently deterring radical forces and controlling the country."