what the word Al Qaeda means?
The base!,
The base was a place held by fighters and assaulted by russian troops, after a long siege the russians were beaten back.
Osama became a hero from this and his legend as some kind of hero fighter was promoted by a short video clip showing him with an AK slung on his shoulder.
He had already become popular for financing lots of humanitarian aid to afghan people.
If the US had listened to Charlie Wilson they would have poured aid into Afghanistan when the Russians pulled out, this would have given the at the time mostly united fighters and mostly united people a base to at least try and build a country from the ashes.
Instead they just sat back and left the afghan people in the mess they were in and it resulted in the anarchy that helped the taliban take hold. Also Osama and friends along with the then mostly united mujahideen felt let down badly after fighting a war by proxy for the US, they never had much love for the US and the west but this gave them new reason to hate.
So after a civil war between various warlords and groups of factions Al Qaeda with its ability to recruit foreign fighters was sheltered in the newly created mostly hardline taliban state with only small enclaves of original mujahideen.
The taliban being accepted due to their ability to bring order and some kind of law to areas previously in chaos due to warlords, the sharia law they imposed and the way the taliban operated was very harsh but the talban gained support because the mujahideen warlords were not able or willing to stop crime only to fight each-other and the population were brutalised by the constant fighting.
In short Javeed average afghan was going for the lesser of two evils, hardline talban but he and his family can at least live in some kind of peace, or constant civil war between mujahideen warlords, Javeed average went for the taliban.