Hugh McManners: Victory is possible – but not by bombing the Afghans 'back into the Stone Age'

The brutally tough terrain of Afghanistan has already claimed the lives of countless British and Russian soldiers, but so far no Americans. Unless the predicted counter-terrorist operations are kept free of political interference, a new "North-West Frontier" war could change that in a very big way.

President Bush is under tremendous pressure to visit vengeance upon the perpetrators of last Tuesday's terrorist attacks. Special Forces on both sides of the Atlantic are preparing for operations on the ground inside Afghanistan. But unless military commanders are allowed to take their time to plan and develop what can only be a long-term military campaign, disaster is assured.

US Special Forces have little experience of counter-terrorist operations – and none at all in arid mountainous regions. Britain's SAS will, however, more than make up for this; Operation Storm, their seven-year campaign (1970-77) in Dhofar against communist insurgents from the Yemen, provides a text book solution. And from 1982 to 1989, SAS men operated inside Afghanistan with the Mujahadin.

The most senior US officers served in Vietnam – a campaign that escalated into a vicious war. If handled incorrectly, any incursion into Afghanistan could quite easily become another Vietnam – only very much worse. The key to success is a combined military-political operation, and an enormous amount of restraint.

Just as the terrorists created mayhem with nothing more than the hideous use of a few Stanley knives, this will not be a high-tech campaign. The USA will not be able to solve the problem with technology and dollars alone. Soldiers' lives will have to be risked. There will be body bags.

Neither Cruise missiles nor Special Forces can be sent into Afghanistan to carry out strikes, sabotage, assault or snatch operations without precise intelligence, which will take time to gather. If innocent people are killed unnecessarily, the West risks alienating what is at the moment a remarkably global coalition of support.

Success will not come after a series of military strikes, but through a long-term counter-terrorist campaign. It is therefore vital to define precisely the aims of the Special Forces operation.

Arresting Osama bin Laden will achieve very little as other more shadowy players were clearly involved, and remain in hiding preparing for the next outrage. Without exact information, destroying every haystack in a remote, desperately poor agricultural country looking for that one man is a dangerous waste of time.

But before covert reconnaissance can begin, in what is generally agreed to be the hardest environment in which to conduct military operations on the planet, an enormous logistic effort must be in place. Within much of Afghanistan, rapid road movement is impossible, and as the Russians discovered to their cost, disastrously easy for small numbers of insurgents to ambush. The key element is therefore a large-scale helicopter force plus air-to-ground strike aircraft, set up in northern Pakistan with forward fuel dumps inside Afghanistan itself.

Helicopters create problems of their own. With much of the terrain more than 3,000 metres above sea level, there is less oxygen and the air is colder and thinner, so they carry less fuel and ammunition and fewer troops. As a result, ferrying operations take much longer. They are also very vulnerable to small arms fire or primitive anti-aircraft missiles, particularly when fired from the sides of steep valleys, and need escorts of attack helicopters and fixed-wing aircraft.

Integral to military action is economic aid, so the small number of terrorists are gradually alienated from the majority of ordinary Afghani people who currently support, feed and house them. Terrorists often use violence on their own supporters as well as their enemies, so if military operations can make ordinary people feel secure, support for the terrorists may suddenly evaporate. What is termed accurate humint (human intelligence) will then start to flow – arrests will follow.

As Western forces move into Afghanistan, they must bring with them improvements for the local people; for example of water supply, medical treatment and food. Alienation of the terrorists must be achieved through the classic process of winning "hearts and minds" – and emphatically NOT, in a phrase beloved by bellicose US senators, by bombing them all back into the Stone Age.

So the Pakistan government delegation's visit to Kabul was the vital first step, to get the Taliban on side. Although it does not seem to have been successful, eventually it may prove to be. Terrorism is a threat to all governments, whatever their political position, and the Taliban may have felt as pressurised from inside Afghanistan to protect the ultra-extremists as they have been by the West to give them up. The Western military operation must make the Taliban feel safe enough to run the risks of co-operation.

The SAS have a well-tried mastery of the political machinations required to walk the tightrope between persuading the terrorists to change sides, and sudden, laser-accurate violence "pour encourager les autres". But their sort of campaign will not succeed if it is going to be micro-managed by fretful politicians in Washington, London or anywhere else. This happened in the Gulf War, when political considerations forced the SAS to go precipitously into Iraq to destroy Scud missiles. A squadron commander was sacked for trying to do things properly; and few if any missiles were destroyed.

As the Western military operation extends its tentacles into Afghanistan, the terrorists will retreat into more remote regions, and there is certain to be a pause for the savage storms and snows of winter. Many will retreat north of the Hindu Kush into Uzbekistan, Tajikistan or into Turkmenistan. It is therefore reasonable to hope that the Russians, who still have influence in these states, will support a combined, long-term operation of this sort, as it might succeed where they so painfully failed.

If this does happen, President Bush's "War" against terrorism will get off to an auspicious start. Terrorists can only survive where there is already inter-governmental antagonism. But when governments swallow their differences and combine forces, there are suddenly no hiding places. The lives lost in Tuesday's atrocities may not be in vain if this level of international co-operation can be achieved. But the military aim must not be compromised by a desire for vengeance – which in both Islam and Christianity belongs only to God.

The author is a former commando, paratrooper and SAS soldier