Nothing has been quite as exciting and as disappointing or even disgusting as the grand drama of this Democratic contest for the nomination. We have seen Barack Obama rise and, with a new tone, make biracial identity a public fact of American life. We have also seen Americans reinvigorated, surging with a refreshing patriotism that is fully aware of the country's shortcomings. We have seen America's history of struggling toward fairness become, perhaps for the first time, a common heritage that crossed lines of color, class, religion, region and sexual identity. In Obama's world, every American can lay claim to...