But sadly, they are this way (and were this way) before, during and after US support. The weapons that they are using to hurt the people of Afghanistan were sold to them by the US. They exist due to our support.
Well, yes and no. The US definitely gave weaponry to the Afghan resitance, like US made Stinger missiles. The US was so eager for retribution for they fought with Russia by proxy in Vietnam that they jumped at the chance. It worked then, but now we see the consequences of that decision. The Afghans destroyed the Russians. When they did, they basically jacked the Russians weapons and have been using them ever since against coalition forces.
And the US knew what type of group they were but at the time they were beneficial.
No, not really. After the Russians left, there were civil wars because of competing ideologies. The most prominent were the Northern Alliance and the Taliban.
Well you can't have it both ways. You can't support a monster, supply it weapons and then question why they are commit horrific acts on their own people.
That logic fails because things change, and no one had the luxury of foresight back then since hindsight is 20/20. That would be like never forgiving the Germans or Japanese because they were a monster then. Things change.
While the US backed them and supplied them weapons, they were doing the same thing to the citizens of Afghanistan. The US turned a blind eye to them torturing citizens because we were using the Taliban and Al Qaeda to fight the Soviets.
There is plenty of suffering the US and all nations turn a blind eye to because intervention is tricky business. You have to prioritize because if either way you play it, you call it a humanitarian mission and they'll accuse you of interventionism, you do nothing they'll accuse of isolationism.
"Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passions, they cannot alter the state of facts and evidence." --John Adams