I had to watch the Obama speech twice to be sure: But at a moment early in his oration, his crowd responded by shouting, “USA! USA!” I’ve been slow to fall for Obama. (After my early infatuation with Wes Clark in 2004, I’ve tried to discipline myself to be slow to fall for all candidates.) Still, his emphasis on the “nation”—one of his most recurrent themes—is also one of his most appealing. I don’t think I’ve ever heard a crowd of Democratic primary voters erupt in a spontaneous display like this. It was a genuinely moving moment, and another leading indicator of his electibility. Liberals who credibly bathe themselves in patriotism greatly increase their chances—and, in this case, prepare themselves well for running against John McCain.

--Frank Foer