[quetzthecoatl]

>Why do we leave so much behind?

because it was part of the deal? It's the same playbook used to equip ISIS back when toppling asad was the objective. It's not like none of these could be dismantled or outright destroyed. That and Taliban was created by none other than US with the help of Pakistan. It's not like US and Taliban are strangers, and surprise surprise, taliban isn't even in the designated terrorist list apparently. You also have UK military head doing PR for Taliban. Taliban takeover was with the approval of US, and weapon transfer was part of the deal.