Little Hawk, the part about keeping political and commercial interests viable is right, but petroleum is not the primary mover for the U. S. although many people blame it. It is for the European economies (or was until the recent turn to Russian area oil and gas). The 'strategic resources' of the Middle East are are of much greater importance to the EU that to the U. S. and Canada; and you do not mention the Suez Canal.

The sole important petroleum source in the Middle East for the U. S. is Saudi Aramco. There have been no real threats to this supply.
Currently, the U. S. gets less than 20 percent of its petroleum from Aramco, and a small amount from Iraq (most going to Europe); the U. S. gets most from Canada, Mexico, Venezuela; a fair amount from southern Africa and South America.

Also of greater importance is the Suez Canal, important to the flow of all commodities world-wide. Perhaps the primary reason the Egyptian army is important to the West.