As I write this, the breaking news is the Taliban are entering Kabul from all sides under orders not to provoke violence. No resistance is being offered by the security forces.
From the day that the West, led by the US but including NATO, sent ground troops into Afghanistan, the mission was doomed to fail. However long we stayed, whatever good we did, however many lives we sacrificed, however many trillions we poured into the social modernisation project, or the nation building dream, Afghanistan would remain what is always has been; unconquerable by external forces.
I said it then, I remark it now. In the end, this time, the collapse comes not because of the military genius of the Taliban (formerly our friends and allies the Mujahidin in the Soviet era) but because once again a totally corrupt political class milked the West for its own narrow advantage of every dollar it could lay its hands on. We turned if not a blind eye, a myopic one. The Kabul government is now falling over because it is rotten to the core.
That is the reason staying a little longer, wishing it had turned out better and all the other hand wringing, while noble and decent, is futile. For those of our own who gave life and limb to support a cause they were told was just and worthy, we owe them a great and irredeemable debt. A debt of honour wrapped in our shame.