By Michael Codner
Director of military sciences, Royal United Services Institute
Troops training with improvised explosive devices at Camp Bastion
Government ministers and military chiefs alike are puzzling over a key question on Afghanistan - how many troops should Britain deploy and for how long?
In his leaked initial assessment of 30 August of the security situation in Afghanistan, General Stanley McChrystal, as commander of US and international security assistance forces, called for an increase in resources, in particular to win the short-term fight to 'gain the initiative and reverse insurgent momentum' in the next 12 months.
Ultimate success will depend on winning the long-term fight, which will require a change in culture to focus on the Afghan people and improvement of the effectiveness of the Afghan security forces.
But it is the short-term need to turn the tide against the Taliban insurgents which is critical.
President Obama is at present considering whether to increase troops from the present figure of 68,000, which includes the surge of 17,000 earlier this year.
Since the arrival of Gen McChrystal the US has accepted a stronger lead in the Afghanistan war in relation to Nato.
For the British government the dilemma is, on the one hand, to put the lid on what could be an unlimited commitment in the face of the economic crisis and shaky popular support for the war.
On the other hand, Gordon Brown is under pressure to show an appropriate level of support for the US by increasing force levels, and to justify to the British people that this is a war that must be won because failure would, as the government claims, open the UK to increased terrorist attack from a secure Afghan base.
Needless to say, the British media have pushed the line that the reluctance to increase troop levels is increasing the risk to the troops themselves.
On Monday the Sun took the opportunity of General Sir Richard Dannatt's investiture as Constable of the Tower of London to have him acknowledge that the military chiefs asked for an additional 2,000 troops earlier in the year and this was rejected by Brown.
The new chief of general staff, Sir David Richards, it is understood, is planning on the basis of an increase of 1,000 troops and this is being considered by government.
Of course the British commitment is only one of a large number of Nato and other nations, and is proportionally and in terms of commitment to combat and military risk in a very difficult region of Afghanistan, far higher than most European countries.
Indeed it has ranked well alongside the US in relation to population and national wealth.
If other allies will not increase their levels and the risk to their forces, does Britain have a particular reason to be exceptional in its commitment?
It led the Nato effort in 2006 when the US was distracted in Iraq, even though the UK still had the problem of Basra province. Indeed the UK was first in support of the US campaign to oust the Taliban in 2001, even though the then US president George W Bush rejected a Nato Article V operation in favour of one that was essentially American-led.
Setting aside the threat of terrorism from a Taliban-dominated Afghanistan to the UK, the problem for this government or any subsequent one goes to the core of British military strategy.
The UK are in Afghanistan, and we were in Bosnia, Sierra Leone, East Timor and Iraq for reasons that relate to the nation's perception of itself as a great power.
It has rebuilt this status economically and militarily since the early 1980s. This status is supported by a good reputation for 'values led' diplomacy and military action.
The nation is particularly dependent on a secure world environment as a trading nation and because of its geostrategic position, its social associations and responsibilities.
International influence is the primary way to a secure world. It can have its greatest effect through the US and this influence must be sustained and developed through a consistent and reliable contribution of useful and self-reliant military forces.
The UK chose to be in Afghanistan in 2001, and to go back in 2006, to a large extent for these reasons.
It now faces the prospect of loss of military and moral reputation from the viewpoints of the US and internationally.
The British people have not experienced the humiliation of deep strategic failure since Suez as others including the US and France have done.
There is a financial and human cost in this strategy which the nation must either pay or accept that it has lost its presumed status and influence and can relax and be a normal European country that does not take hard power seriously (in the Blair construct).
And this is not a tipping point just for Labour.
This strategy is what is left of the remnants of national consensus confirmed in the 1998 strategic defence review but wrecked by the war in Iraq.
A Conservative government would be in the same spot. In order to sustain the national self belief, it too would need to give a good showing in troop levels and equipment in winning the short war.