Greg Sargent has a nice take on the e-mail an Obama campaign official sent mocking Paul Krugman and the “firebaggers.” But whenever I read these periodic eruptions about “the professional left,” my main thought is: if I were a member of the professional left, I would be stoked.

Paul Krugman is one op-ed columnist. Firedog Lake is one Web site. They have readers. But they are not the state of Ohio. Time and again, however, we see evidence that they have gotten deep inside the White House’s head. In letters, in offhand comments, in outbursts at press conferences, in my personal reporting, members of the Obama administration and members of the Obama reelection campaign will let slip that they are dwelling and worrying over these arguments. They may not agree with them. They may not think they’re fair, or sophisticated, or useful. But they’re thinking about them. And if you’re the “professional left,” that’s exactly what you want.