Earthquakes occur suddenly and without clear warning. Political convulsions too come on quickly and surprisingly. When this volume was completed in 1963, I had only a dim premonition of the approaching upheavals. In the following year, we witnessed the assassination of John F. Kennedy, the Republican party's nomination of a defender of "extremism," intense partisan and ideological conflict and the most overwhelming popular victory in American political history.1 In retrospect, it is clear that the campaign of 1964 has shaken the American political system--and the beliefs of American political scientists.
Destructive as they are, earthquakes pass quickly. They leave behind a landscape changed in many aspects but still bearing the general imprint of the past. The political scene of the United States has been altered by the last Presidential race,____________________