ITV News Presenter Tom Bradby reflects on the fall of Kabul and how it compares to the fall of Saigon in the Vietnam War
America lost more than 50,000 soldiers then in a war that killed hundreds of thousands of Vietnamese and ended in scenes of abject humiliation that are still replayed to this day.
But the parallels are apt and numerous.
America’s intervention in both places was predicated on the idea of stopping a global ideology from spreading.
In both countries, endemic corruption meant it was hard to build genuine popular support for the regime, though the government in Kabul was at least democratically elected.
Despite spending enormous sums of money on building up the military capacity of both nations, they ultimately folded without US support.
The speed of the collapse of both countries took the entire foreign and intelligence community in Washington by surprise.
Oh, and both involved the complete humiliation of the world’s global superpower.
By the final days of Saigon, it is fair to say the conflict in Vietnam was widely considered to be the wrong war, in the wrong place, at the wrong time.
But more than 40 years later, some historians might argue that America’s determination to fight the spread of communism in South Vietnam and around the world did contribute to the ultimate collapse of the eastern bloc at the end of the 1980s - (though, for many others, it would have folded anyway and America’s involvement in Vietnam did nothing but sully its international good name).
The coming years will give us a sense of whether the post 9/11 policy-makers can claim anything but suffering came from involvement in Afghanistan.
If the "new" Taliban now in control steers clear of support for international terrorism, perhaps they will, at least, have that argument.
But we also went in there to build a new nation, encouraging many thousands of Afghans to invest their hopes and dreams in us.
And as we watched those desperate people trying to cling to the wings of a departing US transport plane today – scenes that may also be replayed a hundred years from now – it is hard to shake the sense this humiliation is going to cast a very long shadow, particularly as it comes at a time when democratic ideals seem generally in retreat.
In the early '90s, perhaps even long after that, it was possible to believe the concept of western democracy was on the march.
But with the demise of the Arab Spring and the increasing self-confidence of totalitarian states like China, the abject humiliation of the UK and America could hardly come at a worse time.