““Our political solar system, in short, has been characterized not by two equally competing suns, but by a sun and a moon. It is within the majority party that the issues of any particular period arc fought out; while the minority party shines in reflected radiance of the beat thus generated .... Each time one majority sun sets and a new sun arises, the drama of American politics is transformed. Figuratively and literally a new political era begins. For each new majority party brings its own orbit of conflict, its own peculiar rhythm of ethnic antagonisms, its own economic equilibrium, its own sectional balance.””