The big increase in British casualties in southern Afghanistan in the past ten days has enveloped the whole campaign with a sense of foreboding.

Military commanders in Helmand province are insistent that morale remains high. The Taleban’s ruthless exploitation of increasingly sophisticated and deadly improvised explosive devices (IEDs) has, however, made every foot and vehicle patrol a potentially lethal last journey.

Eighty-eight soldiers have been killed by explosions since 2006, one of the most recent yesterday morning when a member of the 2nd Royal Tank Regiment was killed near Nad-e-Ali in central Helmand.

“We have very brave young men fighting the Taleban and are winning the battle but I’m not sure whether we can win the campaign,” General Lord Guthrie of Craigiebank, former Chief of the Defence Staff, told The Times.

Lord Guthrie said the extra 2,000 troops requested by the military but rejected by the Government would have made a difference, “because when we go into villages in Helmand we need to be able to hold the ground to prevent the Taleban from returning”.

The casualty rate has risen in the past ten days as the Taleban react to the presence of 3,000 British troops in parts of Helmand that the Taleban view as their areas of influence and control. Operation Panther’s Claw, begun three weeks ago, is an attempt to clear the Taleban out of central Helmand to create secure zones in which the Afghan people can, on August 20, vote in the presidential election without being intimidated — and with reduced air cover ordered by the new American commander. In response the Taleban have been burying IEDs on all the routes used by British troops in the area using a mixture of “command-wire” and pressure-pad devices.

Lord Guthrie was critical of the level of protection given to the troops. “The personal equipment, such as rifles and helmets, are very good but there is a big gap. There are not enough supply helicopters and not everyone is being transported in properly protected vehicles,” he said.

The only vehicle in Helmand that has shown it can withstand the blast of the IEDS — the heavily armoured Mastiff troop carriers — are impractical for some of the missions in which the British troops are engaged. They are too big for fast manoeuvring. Other vehicles, such as the Viking and Snatch Land Rover, are vulnerable to the roadside bombs, which have increased in size in recent months.

The Taleban are not having it all their own way: many have been killed and there are reports that they have been retreating from areas such as Babaji, north of Lashkar Gah, because of the British-led offensive. However, there remain serious concerns — as outlined by Lord Guthrie — that the British force is neither large enough nor sufficiently well protected to guarantee success in the province.

In Iraq British forces faced the same problem of IEDs, and eventually had to pull out of Basra. In Helmand, however, there are no large cities like Basra. The biggest urban location is Lashkar Gah. The few towns include Sangin, Gereshk and Musa Qala. The Taleban do not congregate in large numbers but drift in and out of the communities, using motorbikes to escape from British troops. Their asymmetric method of attacking the troops has undermined the campaign.

“Some people will no doubt call for the troops to be brought home but that would be wrong and also a betrayal of the sacrifices being made,” Lord Guthrie said, adding: “But one must not forget what the Taleban are supposed to have said, that ‘We have the watches but they have the time’.”

The predicament of the British forces is graphically explained by Sergeant Matthew Parry and LanceSergeant Colin Skitt, both 31, of the Welsh Guards.

Pouring sweat, unwashed for three days, ruddy-faced and peeling viciously in the midday sun, the soldiers said: “They are fighting in sandals with two magazines of ammunition. We’ve got 100lb on our backs trying to chase after them.”

The 1st Welsh Guards have spent the past two months fighting in Nad-e-Ali district of Helmand.The temperature was 40C and 20 men crowded under the only tree for shade as others stood guard outside.

“We’ve lost count of the firefights. The small arms fire is like a game of tennis really,” said Sargeant Parry, “but as soon as we get the big stuff in,” he nodded skyward, “they tend to bug out.”

It’s a tough, frustrating, stoic business. It is also a question of relentless self-discipline and unenviable judgment calls. In another spartan-looking checkpoint, the commander of the Prince of Wales’s Company of the Welsh Guards, Major Giles Harris, 36, sat, radio crackling at his side.

“When we meet the bad guys, we win,” he said. “But it is a continual challenge to balance the effect this has on the civilians in the middle. It is the discipline required not to take the gloves off.

You are asking a guardsman not to empty the magazine of his weapon into the compound wall from which he is being shot at . . . When we call in Apache helicopters they are superb, a great morale boost for the boys. But you think, ‘Did I do the right thing?’ It only takes one stray cannon round and you take two steps back.”

In a tactical directive to the troops under his command, released on Monday, the new commander of Nato forces in Afghanistan, General Stanley McChrystal, wrote: “We must avoid the trap of winning tactical victories — but suffering strategic defeats — by causing civilian casualties or excessive damage and alienating the people . . . The Taleban cannot militarily defeat us, but we can defeat ourselves.”

This is easier said than done when soldiers are facing attacks every day from a largely unseen enemy that fires on them from civilian buildings and morphs in a second from determined attacker to bewildered and terrified- looking local civilian.

Given the choice, all the soldiers would prefer a gunfight to roadside bomb attacks. The bombs are the “worst case scenario” in the words of Lance-Sergeant Waisale Soko, 28, compared with the “bread and butter” of a gunfight.

Soldiers don’t tend to dwell on their losses, except to look away and fall silent at the mention of lost comrades. Some talk about doing their grieving later. Only a few will admit to discreet doubts about what they are doing. “My kid is being born soon,” said one. “What use is it if all you leave your kid is a beret, buff belt and a medal?”

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