Of course we supported the mujahideen freedom fighters but lets ignore the fact the leaders of the taliban were mujahideen fighters. The taliban didn't exist but the leaders existed and leaders went on to form the taliban and start a war. You need to ask yourself, how could the taliban start a war, where did they get weapons from? We may say we didn't but we gave the leaders the weapons to use against their own nation. We allowed them to kickstart with the weapons we gave to them to fight against the soviet union.

https://en.wikipedia.org/wiki/Taliban#Soviet_intervention_in_Afghanistan_(1978%E2%80%931992) Looks under soviet intervention we gave the leaders weapons.