A clearly defined mission; troop strengths and structures composed to fit the task; consolidated public will; the generation of mass and precise execution of force: these are some of the principles of war stated as necessary for victory by the greatest military thinkers of our age.

They all seem dangerously absent in Afghanistan, where General Dan McNeill commands a disparate force of 40,000 Nato troops drawn from 38 nations, each with a different agenda and a varying preparedness to fight.

For one of America’s most senior generals, with experience in counter-insurgency going back to a tour with the Special Forces in Vietnam in 1969, as well as a previous command in Afghanistan, it is difficult to think of a more invidious post — other than that of his comrade in Iraq, General David Petraeus. Yet while General Petraeus is fighting to stave off defeat, General McNeill is fighting for time, the key force with which to hold and invigorate the Afghan people’s support until their country’s security forces are fit to take over the Nato role.

He is the first to admit that he does not know how fast the clock is ticking.

“Can we enjoy that time and have the will of both people, indigenous and the people of the constituent members of the alliance?” he said during an interview with The Times at Nato headquarters in Kabul. “I don’t know the answer to that question.”

The hindrances to his task are enormous, and are represented in part by a coloured checklist framed on the wall of his office. Beside a list of each Nato nation contributing to the Afghan mission are columns denoting their caveats on an array of potential tasks. Some countries, including the US and Britain, seem prepared to do most things that they may be asked. Others are flanked by a patchwork of yellow and red marking.

Yellow denotes that they may consider an operational request from General McNeill once their chief of defence staff or defence ministry has been consulted; red is a straightforward “No, never”. And these are just the basic caveats: there are hundreds filed in total, making the alliance resemble more of a pushme-pull-you co-operative rather than a unified fighting force.

Nato officials admit that some nations will not allow their troops to be involved in direct fighting with the Taleban; others will not operate in the snow. Some refuse to be deployed anywhere near the south or east of the country, where combat is fiercest; others refuse even to patrol at night. Some will fly here but not there; some detain prisoners but others refuse to. The list seems endless.

Using such a force seems akin to halting a time bomb with a Rubik’s Cube built into the fuse assembly. Carl von Clausewitz, the 19th-century military theorist from whom most advanced Western nations draw their war doctrine, would have a fit. “I think he’d say, ‘You’re having some tactical success. I think you’d have greater success if some of the restraints were lifted from you,” General McNeill said.

If Nato is divided, so too is the enemy. Once a composite, predominantly Pashtun force with a cohesive chain of command, since their overthrow in 2001 the Taleban has emerged as a spangled, loose-knit merger of groups hostile to the Karzai Government.

In the south of the country Mullah Omar maintains a weakened control over former Taleban commanders, madrassa students, poppy barons and impoverished fighters disaffected with Kabul’s corruption.

In the east American forces fight tribesmen affiliated to the Haqqani family, old-time jihadists with an ultra-fundamentalist ideology and al-Qaeda support.

Further north the insurgents are predominantly under the command of Gulbuddin Hekmatyar, whose radical Hezbi-i-Islami party brought catastrophe to Kabul during the civil war of the 1990s.

No factions are mutually exclusive or indivisible, and all can be joined in turn by opportunist groups.

Despite their fragmented nature, General McNeill doubted that the insurgent forces were any less ambitious in their hopes than when the Taleban had first ascended to power more than a decade ago. “I don’t think they are any more modest than they were before,” he said, “and I think you’d have to assume that includes Kabul . . . I would not be surprised to hear a moderate’s statement that they want the whole kit and caboodle.”

Reports have surfaced recently in international and local papers concerning secret talks between President Karzai’s Government and the Taleban, the latest in a long line charting covert negotiations to bring an end to the conflict.

Credibly sourced, they referred to a tentative list of Taleban demands including the release of prisoners, control of ten southern provinces and a timetable for the withdrawal of foreign troops. While acknowledging the need to negotiate with insurgents, General McNeill was critical of the timing of the reports.

“I don’t think it is helpful to the alliance,” he said. “I think it gives people false expectations and I believe it causes some people to think that a solution is imminent, and I don’t see it that way. I’d be disingenuous if I thought some solution was imminent. I don’t.”

Undermined by the divided nature of the insurgents, the credibility of negotiations is further shadowed by the precedent of Musa Qala, where British commanders and Afghan officials struck a disastrous deal with the Taleban last year.

The British agreed to withdraw their besieged troops from the town so long as the Taleban did the same. The Taleban returned to the town within 72 hours. It remained an insurgent sanctuary to this day, something that Nato troops in Helmand had since paid a price for, General McNeill said.

Which leaves the general reliant, for the time being, on his more trusted Nato elements to fight the counterinsurgency, while trying to utilise the more timorous units as best he can.

“We have to do what we can when we can do it,” he said, “knowing that the clock runs out and the last page comes up in the counter one day.”

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