Fifteen years on from the attack on the Twin Towers, the moment that threw the West into the War on Terror.
And by coincidence Sunday also marked ten years since I was ordered into battle as part of that war.
My mission should have been straightforward: to join a handful of other British soldiers – a motley assortment of regulars and reservists, from infantrymen to signallers to medics – whose job it was to help the Afghan army and police retake from the Taliban a non-descript, but strategically important kalay deep in the south of Helmand Province.
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Once secured we were to hold Garmsir for 24 hours until relieved by a larger force – only the relief never arrived.
After a bloody struggle we recaptured the outpost, but a week later we were still there, besieged.
Day in, day out, we fought for survival. I took my first life in Garmsir, and a few more after that, some at close quarters.
This was not killing for killings sake nor was it something to boast about. It was war, and the men I killed were intent on killing me.
After a week I was one of just three British troops who remained in Garmsir. But we were not totally without help, our Afghan colleagues fighting at our shoulder including Sher-Wali, a Pashtun Afghan and major in the National Police Force.
Sher-Wali had history. He’d fought with the Mujahideen against the Russians and had initially sided with the Taliban when they first took over his country. But growing disillusionment with his new masters meant he was now pitted against them as part of the Afghan Government’s campaign against the insurgency.
He was not an opportunist; simply someone who wanted the best for his family and his people and all too often found himself bitterly disappointed by those who promised the earth and delivered dust.
I formed a strong friendship with Sher-Wali. We shared our food, our stories. We fought side by side and on more than one occasion Sher-Wali saved my life, in one incident shielding me from the explosive yield of a rocket propelled grenade with his own body.
He was and remains the bravest and most noble man I have ever known.
In the most difficult of circumstances he fought ferociously beside a man he knew little about who came from a culture he didn’t understand, but in whom he had placed his trust.
At the last it was he, not I, who paid the highest price of all. Sher-Wali died on the final day of the engagement, carrying out my orders.
For me it was a body blow and when we departed back to base – our Royal Marine Commando relief having turned up a fortnight later than we expected – it was with a mood of melancholy not elation.
Driving into Camp Bastion the faces of those whose entire Afghan experience revolved around this sprawling encampment exhibited shock at the sight of us.
Our single remaining unarmoured Land Rover had been peppered by shrapnel and with numerous entry and exit bullet holes, the ballistic matting long since torn off by Taliban firepower, a hole the size of a fiat bored into the driver’s headrest evidence of a large-calibre round striking its mark.
Everything was covered with a fine film of Afghan desert dust, lending us humans a ghostly appearance, though not so much so that it disguised the dirt, blood and human waste that stained our uniforms.
The strain of the experience showed in our eyes, framed as they were by furrowed brows, matted beards and crazy hair.
For my actions in Garmsir I was awarded the Military Cross. It still arouses in me conflicting senses of pride and shame.
I was not alone in being decorated and our clutch of honours – two MCs, a Conspicuous Gallantry Cross and a Mention in Dispatches - made this patrol the most decorated since the ill-fated ‘Bravo Two Zero’ during the first Gulf War.
The sights, sounds and smells of ten years ago linger with me now. But the more intense memories are those of the people I served alongside. Most of all I remember Major Sher-Wali: his smile, his presence and his loyalty.
He died fighting on his own soil. I believe in what we did in Afghanistan, but it was only ever an interlude for me.
I had a way out, an escape route, God willing I would return home after a six-month tour. Sher-Wali was at home. His fight was existential. Mine was a job. Yet because of people like Sher-Wali Garmsir has stayed with me and I returned to Afghanistan to fight on two more occasions.
Physically I have never returned to Garmsir. Mentally I have never really left.
• Doug Beattie MC joined the Army as a 16-year-old junior soldier. He served for 34 years rising through the ranks from ranger to captain while serving in Northern Ireland, Bosnia, Kosovo, Iraq and Afghanistan. He was awarded the Queens Commendation for Bravery during the invasion of Iraq and the Military Cross for his first of three tours of duty in Afghanistan. He is now an Ulster Unionist member of the Northern Ireland Assembly