Atrios says he's not sure he buys the presidential-run-embitterment theory of Lieberman's lameness.

I'm really not sure I buy the "Joe got all pouty when no one wanted him to be president" theory. He was pretty wankerific before the presidential primary campaign heated up (and, of course, during it.)

True enough. I'd only add that Joe's rejection in the primaries was pretty evident from the outset. So pretty much everything after mid-late 2003, in my book at least, comes in the embitterment era.