“So why doesn’t the United States fly apart at the seams? James Madison may have had it right when he argued that a large, decentralized republic spread over a vast territory was more likely to survive than one confined to a much smaller landmass. A sprawling, diverse nation like the United States would necessarily encompass so vast a variety of people that no single group could consistently impose its will on the others. In Madison’s pragmatic if paradoxical vision, our very differences would keep us together. The nation would remain united because no bloc or faction can command sufficient political power to divide it and destroy the union.
“Of course, Madison couldn’t foresee the conflict over slavery, when two distinct sections of the country went to war over their differences. But this has been the exception, not the rule. Today, the nation is rarely, if ever, united on any single political issue. Our loyalties are too divided, too fractured and too unpredictable. Our diversity divides us, but in the process, guarantees that the larger union endures.”