David Sirota identifies a crucial problem with President Obama’s engagement on behalf of incumbents in Democratic Senate primaries: he’s stymieing primaries of people that are holding up his legislative agenda. Or, more specifically, he’s squashing primaries that would have the effect of either moving the incumbent to the left or replacing him with a more liberal Senator.

So, again, why is the White House trying to crush primaries? I’m not expecting him to back primary challengers…but why is he trying to crush them, instead of simply staying out of the races entirely? I mean, I get why incumbent Senators or House members don’t want to face primaries – they just want an easy ride. The vexing question is why the president would try to help them crush primaries, when those primaries would help it pass its legislative agenda?

In Sirota’s column on the same subject,  he gives a very harsh critique of Obama’s justifications for trying to crush these primaries.

Hence, in trying to prevent or weaken primaries against incumbents, Obama is not merely signaling a royalist’s disdain for local democracy. He is exposing a corrupted pol’s willingness to prioritize country club etiquette over policy results. If his agenda ends up being killed, that cynical choice will be a key cause of death.

It’s what the Democratic elite does – protect the members of their club from the indignant Democratic rabble. It’s unfortunate that a President who waged a successful primary campaign as an outsider with little experience would so quickly slide into the mold of the people he came to Washington to change.

Arguably the best thing that happened to the chances of Obama’s agenda succeeding, at least on health care and labor reform, was Joe Sestak’s decision to primary Arlen Specter from the left. In the course of this year, Specter moved from opposing a public option to supporting single-payer health care. That would simply not have been possibly if Specter wasn’t fighting for his political life in a Democratic primary. He moved from being an opponent to the health reform policy package Obama supports to being an advocate for one even stronger than what is under debate in Washington.

That is what makes Obama’s efforts to quash primaries in Pennsylvania and Colorado and New York so odd. It undermines his agenda to have more conservative Democrats in the Senate, especially ones that are not being challenged to move to the left by primaries. Even if the liberalism of Specter, Gillibrand, and Bennett is temporary, it is better than nothing, as it ensures that at lest 25-50% of Obama’s first term is spent with these people behaving like liberal Democrats and not moderate Republicans.  The only explanation that I see is that Obama doesn’t believe in primaries; he supports “kicking away the ladder” after he and his peers have climbed up it. Who knew that the President would have such an aversion to democracy in the Democratic Party?