There are no ifs and buts from Klein (a wholly inappropriate name for the author of the piece!):

With the netroots having proved they can generate an existential challenge to a safe-seeming incumbent, actually defeating Lieberman would be little beyond icing on the cake. Moving forward, a Lieberman victory would do nothing to blur the traumatic memory of his near-loss. And that gives the netroots an extraordinary amount of power, vaulting them into a rarified realm occupied by only the strongest interest groups.

That sounds to me like it comes from the same factory that gave us

My belief is we will, in fact, be greeted as liberators.

Why should Klein think that lefties are (or will be) in need of a pep rally?

(And will they necessarily be pleased to find Klein issuing threats on their behalf?)

And - even assuming that the netroots (whoever they are) obtain the power he suggests, I'm distinctly unclear which Dem pols can expect to be liquidated at the hands of the online Ministry of Love, and on what basis the selection will be made.

How about this for totalitarian rule-making:

Rather than requiring submission to a certain set of policy initiatives, they'll demand unity in certain moments of partisan showdown.

Will notice be given of these certain moments of partisan showdown to give pols a chance to conform to netroot demands?

Or will they be required to show themselves in tune with the thinking of their new masters by guessing which moments are certain moments?

Klein explains why Lieberman fell foul of the rules:

What so rankled about Lieberman was his willingness to abandon ship when steady hands were most necessary -- he was always the first to compromise on judicial nominees, or flirt with Social Security privatization, or scold critics of the Iraq War.

Always is not a terribly helpful word to use in the context - unless there's a Ministry of Truth fully functioning on your behalf. Otherwise, dissidents with Nexis access might check and find some cases when he wasn't the first.

Plus - what about the one who was second?

And - what's the point of these netroots threats?

Klein says

The effect of this will not necessarily be a more liberal Democratic party, but a more unified one. Partisan pride, not progressive policies, will be the currency with which savvy incumbents pay off the angry online villagers.

Is that what those villagers really want? Polished jackboots in perfect synchronicity, and bugger the universal health care?

Of course, Klein may have slipped in his Onion copy by mistake. Here's hoping...