Did I misidentify the problem that resulted in sacrificing instead of fighting? Since you pointed out the problem with rules of engagement, I would think you do get it to an extent. I don’t know if you agree that generals should fight even when the ruler (in this case the POTUS and his administration) tells them not to, in the case of fighting assuring victory that is.
If you want to invite more attacks on the home soil, the proverbial declaring of victory and running away surely is the way to do it. They will not leave us alone.
Staying in Afghanistan or leaving will not determine whether these animals will leave us alone. IMHO
Interesting question isn't it. If the German armor under Rundstedt had not halted south of Dunkirk on Hitler's orders, but rather gone full speed across the bridgeheads over the canals and destroyed the British/French/Belgian armies, there would have been no miracle evacuation at Dunkirk, Britain would have had to pull out of the war as a ground fighting force, and history would have been very different.
Makes one wonder.