To understand history we must first unlearn it. Or, more accurately, we must unlearn canonized history. That is certainly the case if we are to understand U.S. entry into World War II—the last “good war” the United States fought; perhaps the only war not yet subjected fully to the revision of opinion that has been the lot of other contemporary wars. Bruce Russett's No Clear and present Danger. A Skeptical View of the U.S. Entry Into World War II takes us a long way in examining critically whether U.S. entry into that war was justified, yet it received much less attention than it deserved when it appeared in 1972.