The Taliban won this one fair and square - by paying off anyone who would've threatened their advance. They didn't need a magical Sun Tzu strategy - they literally went door to door and either bribed or threatened everybody until they accepted them as the rightful authority in the region, they've been doing that for the last 20 years, what'd people think would happen?
https://www.vice.com/en/article/epn...-threatened-their-way-to-power-in-afghanistan
While the coalition troops were busy dropping bombs on terrorists, the Taliban was selling rights to rare earth metal mining to China and Russia, and they've made stacks of money from that and bribery. It's painfully obvious where they're getting their funding from.
https://www.cnn.com/2021/08/18/business/afghanistan-lithium-rare-earths-mining/index.html
Now, quick math. The war in Afghanistan cost a grand total of 2 trillion dollars. The population of Afghanistan is somewhere around 38 million.
$2 trillion / 38 million = $52631.57
So, instead of all this fighting, the government could've gone door to door 20 years ago and could've given every single citizen of Afghanistan 52 grand - do you think the country would've been more or less stable? I'm just asking questions, since it seems that the coalition is just dropping exploding money, and losing.