As troops withdraw from Afghanistan enemies must be rubbing their hands - Patrick Mercer

Once you withdraw foreign security forces there will only be one outcome: this mountain stronghold will always be strategically vital and deeply volatile.

When I last visited Afghanistan in 2009, I was appalled to find that the British garrison had only a slender understanding of what had happened to their predecessors in the Helmand Valley in 1880.

Those Victorians were wiped out, comprehensively ground into the dust by a powerful Persian/Afghan force that was contesting the road to Kandahar in just the same way that the Taliban continue to do today.

Now, anyone with a grasp of our history will know that twice in the 19th century, and once in the 20th century, there were British incursions into Afghanistan which it is currently fashionable to denounce as disasters. Certainly, casualties were taken, but politically they succeeded – because they didn’t try to annex the place.

No, the only operation which might be described as disastrous is the 20-year occupation which is about to end. I’m not sure that’s fair, though, because no one has ever admitted what the Allies’ real aim was.

A hundred-odd years ago it was relatively simple: Britain has to keep the Russians at bay and pacify various warring factions whom St Petersberg backed in order to protect imperial India.

By 2001, though, things had changed.

There were no demands of empire and Russia was a potent, but different player whose own defeat in Afghanistan had been critical in the fall of the Soviet empire.

At the time I listened in the Commons as Tony Blair and his Ministers flailed about trying to justify military action.

There was no formal mission statement that I could discover, but British troops were going first to eradicate the threat to our streets from 5,000 miles away, then to destroy the opium trade and then, extraordinarily, the allow women’s rights to flourish. It was all nonsense.

I believe the real reason was – and still is – wholly legitimate. Pakistan has nuclear weapons, almost all of which are stored near the Afghan border as far away from her bitter enemy, India, as possible.

She’s also deeply unstable, with embedded links to the Taliban and other terrorists – remember, Osama bin Laden was sheltered there.

So, what happens if one of these sites is raided and the nuclear material used against the west? That’s why Allied troops have had to be kept close at hand.

But, in 2011, President Barack Obama’s concept to draw down US combat forces was dangerously misconceived. In June he announced that there would be significant withdrawals by December, thus advertising his plans to his enemies and provoking calls for his court martial as Commander in Chief.

That never happened but, predictably, the situation got much worse and Allied troops had to stay.

Then, President Donald Trump planned something similar.

He wanted to halve the US presence there before President Joe Biden took over earlier this year, even though his own Senate leader, Mitch McConnell, said this would, “hurt our allies and delight the people who wish us harm”.

Now, President Biden’s gone further.

With breathtaking crassness the date of September 11, 2021, has been chosen for the final withdrawal, cementing the idea that the grievous deaths 20 years earlier have led to nothing but further carnage, waste and defeat.

But what of our strategy? Well, in line with US draw downs, it was announced in 2014 that all British combat forces would be removed.

This provoked me to ask the then Secretary of State for Defence what plans were being made to re-intervene. I got a spluttered, choleric reply, but if I were still in the Commons I’d ask exactly the same question once more.

Of course, this country will always follow in the wake of US foreign policy, although the difference between our influence in 2014 and today is stark.

Britain had 9,500 forces in Afghanistan at the height of the conflict whilst also fighting shoulder-to-shoulder with the US in Iraq.

Then this dwindled to a handful whilst now – and here’s the rub – we no longer have forces large enough even to stand alongside our allies in another intervention.

But, will that really be necessary?

Well, I think it most certainly will, but whether it actually happens is a wholly different matter.

With our democracies sundered, our economies shattered and our acceptance of risk at an all-time low, I wonder if we will ever be willing to defend ourselves again?

Our enemies must be rubbing their hands.