This is akin to arguing that the USSR fought the US in Afghanistan. It's known that we armed and helped the various groups active there at the time. It's also pretty well established we had only a handful of people on the ground there at any point in time. Had the USSR actually fought the US at this point in time, the resulting combat would have been the most significant combat engagements of the 20th century.

Everyone knows Pakistan funded the insurgency. Pakistan has no interest in actually running Afghanistan. It's a buffer state for them. The US has no real interest in trying to get Pakistan to stop this. It's a failure of domestic politics that we didn't drop pack up a few weeks after it became obvious Bin Laden was not there.