Um... Dana?

Dana Milbank warns that imposing any consequence on Joe Lieberman for what Dana describes as a career-long pattern of backstabbing his former party would put the Democrats on the same path as the Republicans have taken:

Republicans, who recently floated a purity test for GOP candidates, know where this road leads: to a 40-member minority in the Senate. If Democrats wish to remain the majority party, they should avoid the loyalty trap. Lieberman may be a monster, but he's their monster.

Um... Dana? Lieberman's not a member of the Democratic Party. He deliberately chose not to change his party affiliation after his reelection. He is talking about running in the next election as a Republican.

And you're way too smart to be making this argument - Lieberman has already been shown exceptional largesse. In history, how many politicians have been allowed to actively campaign for the opposition in a national election, giving a full-throated endorsement of the opposition party's leader, then face no meaningful consequence when their preferred candidate lost?

Also, it's not an ideological litmus test to insist that members of your party, or those who caucus with you, actually support your party and not threaten to filibuster its most important legislative initiatives. That's basic "party discipline". Why do you think we have political parties if you think that everything that comes after election is legitimately an every man for himself free-for-all?

You know, Dana, I agree with you on this: Lieberman has always been a self-serving, narcissistic wretch. But I think it's well past the time where it makes sense for the Democratic Party to stick with the devil they know. He certainly hasn't stuck with them.