It was a deeply substantive speech, full of policy detail, full of people other than the candidate, centered overwhelmingly on domestic economic anxiety. It was a liberal speech, more unabashedly, unashamedly liberal than any Democratic acceptance speech since the great era of American liberalism. But it made the case for that liberalism - in the context of the decline of the American dream, and the rise of cynicism and the collapse of cultural unity. His ability to...