I image almost all of America was surprised to learn that former General and now Secretary of Defense Mattis said we cannot have a military victory in Afghanistan, I remember the uproar when Obama said we would reduce troop levels by a certain time. Where is that uproar by those same people? Oops, they are in power now!
How can we send troops to a combat situation after we tell them you can’t win so don’t get hurt too bad. This reminds me of Viet Nam when that war was mismanaged. Nixon kept putting troops in after he knew he had lost the PR war and thus invigorated the North Vietnamese leadership to continue. Now we have a similar situation.
An old axiom of military training is leaders fight the last war instead of planning for the next one. We pulled out of Afghanistan before winning there to move those troops to Iraq. We mismanaged the Sunnis causing the Iraq Civil War. JFK, LBJ, Nixon, Bush II, and now Trump thought more of not losing on their watch than saving our troops. Obama tried to get out of Afghanistan but its stability was in question. He pulled troops out of Iraq because we could not get a treaty keeping them from Iraqi law for any crimes the Iraqis considered an American Trooper committed.
Alexander, the Great, discovered the only way to beat the fierce Afghans was to marry the daughter of the biggest tribe. That sounds like a possibility for a President with a ticked off third wife!