There are many illegitimate reasons for the U.S. to have begun killing people in the Middle East.  They include bigotry, control of oil and a Middle East country's resistance to U.S. imperialism.   Lee Camp offers another reason, the dominance of the U.S. dollar.  He argues that this factor has been behind the U.S. attacks of Libya and Iraq, and it is the reason the U.S. is now posturing to attack Iran.  See the first 11 minutes of a recent episode of Lee Camp's Redacted Tonight. One might wonder how difficult it would be to drum up a fake excuse to start a war in the U.S. It's not difficult, once the President decides to go to war behind closed doors.  This is a time-tested prescription, addressed in the video "War Made Easy." Chris Hedges discusses the intoxicating attraction of war:

The enduring attraction of war is this: Even with its destruction and carnage it can give us what we long for in life. It can give us purpose, meaning, a reason for living. Only when we are in the midst of conflict does the shallowness and vapidness of much of our lives become apparent. Trivia dominates our conversations and increasingly our airwaves. And war is an enticing elixir. It gives us resolve, a cause. It allows us to be noble.

Therefore, it's not going to be difficult for the U.S. to publicly justify a war with Iran, especially given the detached electorate, given the U.S. public's distaste for all things Muslim and the warmongers President Trump has gathered as his primary advisors.