With the launching of the US-backed military intervention in Yemen, virtually the entire Middle East is engulfed by military conflict, a state of affairs that has no precedent, with the possible exception of the two world wars fought in the 20th century. Washington’s pursuit of policies from one conflict to the next that are seemingly at odds with one another has provoked mounting expressions of concern from major US think tanks and editorial boards—not to mention nominal allies in Europe—over “strategic incoherence.” To describe as glaring the contradictions that riddle US foreign policy in the Middle East does not do...