There are usually one-line reasons given for the cause of wars. The American Civil War, for instance, was "to free the slaves" or "to protect states rights" depending on the side. "Protecting our nation" has always been popular. Levy (political science, Rutgers University) and Thompson (political science, Indiana University) know that there are no facile answers to the causes of war. In their insightful and informed study, they examine a number of theories about wars and subject them to rigorous tests, pointing out the flaws in each. Rather than propose their own theory, the authors admit that the topic is, so far, too complex to give a grand unified theory of reasons for conflict. However, the analysis does uncover some interesting facts, the predominant being that democracies don't go to war against each other. While war has traditionally been between two nations, Levy and Thompson also look at civil wars and the "new wars" of international terrorism. Along the way are examples from recent history that may surprise the reader. At the very least, every member of Congress and the State Department should study this report. Annotation ©2010 Book News, Inc., Portland, OR (booknews.com)