The driving force for the US misadventures in the last 40 years has been the dying economic belief in globalism. Globalism is really just a philosophical extension of 17th and 18th century British mercantilism. Unfortunately we bought into it wholeheartedly.
In the end this has led us into colonialism and imperialism, not just in Iraq but also in S. America and Asia. If it were not for the Chinese and Indian resistance we probably would have already established a larger military presence in Asia and would have bled them more than we have.
The tough part is that globalism does not work in the intermediate and long term because it tends to ignore all facets of government except for economics. As it falls apart countries tend to become insecure; more war and death entail. A good model for what can happen is Europe in the 10 years prior to WWI.
Less politely. The guys that the US people put in power are neo-fascists or neo-colonialists with a belief that the world's resources and people belong to a corporate state and that they will govern accordingly. In their view may the gods help those who disagree - we are only chattel in the generation of their profits. As such we are of less value than machines and natural resources.
The New World Order looks an awful lot like the Old World Order, but with more means of social control.
A good introduction to what we are up against is John Ralston Saul's book, The Collapse of Globalism. Would also suggest a review of European history for the period 1890 to 1914.
It might help us formulate some strategies and leadership to get us out of this mess without another major war.