In orange, half of America's GDP; in blue, the other half. While the population of the country is much more evenly dispersed, its contributions to the economy aren't.
Of course, the distribution is centered around cities, which affects the skew, but not as dramatically as this. You can spin it so many ways politically, though I won't bother here—that's what you're here for, right?—but it's a stark reminder that the economic activity of the country is wildly uneven. [Expert Market via Visual.ly]
Update: There is a lot that is not correct with this map, including the absence of several major cities and what appear to be misplaced locations. It's our policy not to remove posts once they're up, but feel free to ignore this one.