Exclusive Newsnight report

By Stephen Grey BBC Newsnight

The war in southern Afghanistan has all the ferocity of a conventional war; a clearly-defined enemy, the Taliban, still has the strength and confidence to fight British and other allied forces on a daily basis in open combat.

In response to the threat, Nato forces fight back with some of the most deadly weapons in their modern arsenal: from the automatic rifles and heavy machine guns of their infantrymen, precision artillery, to aerial assaults from helicopters and airplanes.

Americans have been the victims time and again of suicide attacks British soldier

But, as I saw first hand, the battle in Helmand province is more than simply open warfare. It has all the complexity of a modern counter-insurgency waged by a coalition on foreign territory.

I was embedded for the Sunday Times last December with the 2nd battalion, the Yorkshire Regiment (the Green Howards) and I recorded this film, my first effort in wielding a video camera, as they took part in one of the biggest British military offensives since the invasion of Iraq in 2003.

The target was the town of Musa Qala, a Taliban stronghold in northern Helmand which British forces had defended in 2006 from waves of Taliban attacks at a cost of seven British lives but from where they had controversially withdrawn. Now, they were returning in force.

Stephen Grey was embedded with the Yorkshire Regiment

The job of Green Howards was to act as mentors for the Afghan National Army, in effect leading them into battle.

It was difficult and dangerous work because, while the Afghans military may be gaining in strength, their soldiers are a long way short of being able to defeat the Taliban on their own; their ranks include many hardened and brave fighters, but also some who prefer to stay as far from the action as possible � and smoke hashish.

That was not the end of the complexities - they also worked alongside American troops who have different rules of engagement, and all are fighting a conflict against an enemy that doesn't wear a uniform, making it hard to work sometimes to identify who is a Taliban fighter and who is a local villager trying to stay out of trouble.

Human shields

All this became apparent as on 7 December as we approached the village of Deh Zohr-e-Sofia, on the outskirts of Musa Qala. Our attack was a feint: we were acting as bait to draw the Taliban to the south while the American 82 Airborne landed by helicopter to the north.

But there was a complicating factor: as we advanced across open ground, we saw families of refugees fleeing Musa Qala in trucks and cars loaded with their possessions.

Just as two of such vehicles were being stopped and checked for hidden weapons, the Taliban opened fire, sending us diving for what little cover there was and marking the beginning of a gun battle that continued for several hours.

The offensive was one of the biggest since the invasion of Iraq in 2003

As this film I recorded shows, in the midst of the fighting, the two refugee vehicles drove in panic away from the village - but straight towards two American Humvees which opened fire, fearing the ever-present threat of suicide bombs.

Three of the civilians were killed, and two children and a woman injured.

Of Nato troops, it's the Americans who have lost the most men in combat and they play by different rules.

But British soldiers I was with had some sympathy for their tactics.

"Americans have been the victims time and again of suicide attacks," said one.

Another argued that the civilians had in effect been "human shields" and had been "deliberately forced to drive towards us - probably against their will - and used as a screen to attack".

In the operation that continued, ending in the Afghan flag raised on 12 December in Musa Qala centre, there were more casualties that followed.

British soldiers face difficult choices every day

Among them were two British soldiers, including Sgt Lee Johnson of B Company, the Green Howards. He was killed when a mine exploded under his vehicle within 30 yards of where I was standing.

Overall, the plan to recapture Musa Qala had been conceived to steadily ratchet up pressure on the enemy - encouraging the Taliban to flee rather than stand and fight in the town centre; it seemed to work, so causing the minimum destruction of property or harm to civilians.

To win this war, the British have to be seen as fighting for the Afghan people, not against them.

But, when fighting an insurgency, it's the enemy that usually chooses the battlefield, and it's often a populated one.

There is always a big risk that innocents will end up getting hurt. British commanders and soldiers have to make some hard choices each day.