While you are absolutely correct about the points you made, the war is not dependent on these.
The logic is not military, but from the point of view of a scam artist who has every incentive to continue.
It will not matter if USA forces die by the thousands achieving nothing; it does not matter if the oil hits empty for domestic use. Nothing matters but profits for a very few.
Quite literally the USA could be reduced to sail boats with troops armed with only swords, and be killed out at sea. As long as the USA can bomb in the area, with any aircraft: money can be had