For all we know our military had multiple plans and saw this as the best option given the circumstances. I'm open to looking at other possibilities. Let's say the Afghans didn't surrender and had actually fought the Taliban, their president stayed, etc.......... Financially, it would make no difference to us. That money would still be gone.
Also from what I've read, some part of that $83 billion figure was "training", so it literally cannot be taken back.... As far as the guns.. eh.. We're more or less good on guns. Besides how many currently are already here for the military or consumer, we manufacture roughly 22,000 guns in America EVERY DAY. That's 2 guns for every newborn baby in America. We'll be ok.
Anyways yes, here we are. Leaving that $300 million dollar per day money pit... Good.