Our take of winning and losing is clouded by WWII, were we had a complete victory, unconditional surrender. In the history of war fare, this is not the norm.
So I would say the following:
Korea: actually should be considered a win. Korea was divided on the 38th parallel after WWII. Birth Korea invaded South Korea. We liberated South Korea and then signed an armistice. Who failed? It seems the North.
Vietnam:. Agreed, that us a loss
Iraq:. We invaded with the intent of overthrowing Hussein, this was accomplished. Then we stayed and fighting continued, but against other foes. A draw, in my mind.
Afghanistan:. A Taliban government was hardoring terrorist bases used to attack us on 9/11. We overthrew that government, and actually accomplished quite a bit as far as changing their society. But the Taliban fights on and we end up with a negotiated settlement. They have lost power, we accomplished much if what we wanted. Hard to say it’s a loss, one could argue it’s a win. Again, the idea that you only win when your enemy us annihilated and you can peacefully control a foreign country is rather rare.