Sydney Blumenthal nails it

Here's part of his Lieberman post-mortem:

Aug. 09, 2006 | Joe Lieberman's fall from grace appears straightforward. In Connecticut, where George W. Bush and his war are intensely disliked, Lieberman stationed himself as the president's defender. But Lieberman's precipitous descent from nomination as vice president to rejection by his home state partisans is also something of a mystery.

Lieberman was once the most attractive and promising Democrat in his state, his grasp of political realities subtle and sinuous. But he became scornful of disagreement, parading himself as a moral paragon to whom voters should be privileged to pay deference. The elevation of his sanctimony was accompanied by the loss of his political sense.

And here's the rest: Joe's fall from grace