Trende has developed a reputation as one of the country’s most promising younger political analysts. In this iconoclastic, detailed study, he takes on one of the most visible and widely supported theories in contemporary American politics: the idea that periodic realignments of voters produce stable political eras in which one party is the natural party of government (the “sun party”) and the other major party (the “moon party”) is only rarely able to prevail. Trende makes a strong argument that American politics is surprisingly fluid and that the widespread belief in the existence of distinct eras -- such as the New Deal era, from 1932 to 1968, or the era of Republican ascendance, from Richard Nixon through George W. Bush -- does not hold up under close examination. Trende also takes on the more recent claims that either the Democrats or the Republicans are headed for long-term political dominance. Instead, he argues, coalitions will continue to fray as new issues emerge and old ones fade, groups of voters shift their allegiances, and the parties adapt to changing electoral circumstances.