The deepest and unhealthiest divide in American politics is not the one that separates Republicans from Democrats or conservatives from liberals. It is the gulf between Insiders and Outsiders -- between the incumbents who treat public office as private property and the increasingly neutered electorate in whose name they claim to act. You may have learned in ninth-grade civics class that lawmakers are the people's servants, temporarily entrusted with power that the people can take back at any time. But ninth grade is light-years away from the reality of Congress and the statehouses today, where many legislators regard their positions...