That didn't give the army generals a reason d'être to justify a large army budget for the next couple of decades though. We went boots on the ground for one reason. Large land armies have become irrelevant.
I hope those in the decision chain hang their head in shame over the suffering they caused, that's on both sides.
It's very easy to be wise after the event, but during the early years (before the West was distracted by Iraq) there was widespread public support for our efforts in rebuilding Afghanistan. Indeed, it was often said that Iraq was the 'bad' war, while Afghanistan was the 'good' war.