JAMES TARANTO: Donk Fight! Republicans aren’t the only ones with nasty intraparty disputes.

Liberal journalists love writing about divisions in the Republican Party–social conservatives vs. moderates, Tea Party vs. establishment, and so forth. That gives stories about Democratic infighting a man-bites-donk quality. One such story is a feud between Markos “Kos” Moulitsas, the Angry Left’s answer to the Htoo twins, and Matt Bennett and Jim Kessler of Third Way, a Democratic think tank that describes itself as representing “Americans in the ‘vital center.’ ”

It started with a Moulitsas post in which he urged Koz Kidz, as readers of his eponymous website are called, to buck up. Headline: “Ten Years of Political Progress. And Yes, We’ve Made Progress.”

That seems obvious enough. A decade ago, Republicans controlled both houses of Congress and the dreaded George W. Bush was about to be re-elected. But he doesn’t mean Democrats have made progress; he means left-wing Democrats have made progress.

Well, Russia’s resurgent and the United States is in retreat worldwide. Plus, lots more Americans are on welfare. So…