We went in to get Bin Laden. He has been dead for a while; killed next door in Pakistan. Bid Laden doesn’t explain why we are still there. We are now have fighting men on both sides who were not born when this war started. What force keeps this thing going? Whatever or whoever it is, it needs to be removed from its position of influence.
The same force that keeps us in Germany and Japan 75 years after WWII -- it is in our strategic interest to be there.
We're not in a war in Afghanistan and haven't been since Bin Laden was killed.