Glenn Greenwald scoffs at those who claim that Obama lacks the power to bend Senators to his will:

What happened in this race also gives the lie to the insufferable excuse we've been hearing for the last 18 months from countless Obama defenders:  namely, if the Senate doesn't have 60 votes to pass good legislation, it's not Obama's fault because he has no leverage over these conservative Senators.  It was always obvious what an absurd joke that claim was; the very idea of The Impotent, Helpless President, presiding over a vast government and party apparatus, was laughable.  But now, in light of Arkansas, nobody should ever be willing to utter that again with a straight face.

Jonathan Bernstein corrects him:

I don't know how to respond to this nicely: this is ignorant nonsense that betrays a deep lack of understanding of how the government of the United States works. ...

So a clever and hard-working president can get some -- some! -- of the things he wants.  As Matt Yglesias notes, all the pressure in the world on Blanche Lincoln wasn't going to make much of a difference when it came to health care reform.  That's because she wasn't the 60th vote -- in fact, she and Mary Landrieu were probably votes numbers 56 and 57, something like that.  More to the point, on the public option (which is presumably Greenwald's complaint, since as he might recall the actual, landmark health care bill did, as a matter of historic record, actually pass), well, the public option only had somewhere around 51, 52, or 53 votes in the Senate.  Oh, and that's for a very weak public option, something that the actual policy experts believed was largely inconsequential.  For better or worse, a "robust" public option didn't have the votes in the House, and certainly didn't have the votes in the Senate -- a strong public option had somewhere between 45 and 48 votes in the Senate, by my count.

Could Barack Obama have threatened a dozen Democrats with primaries?   That's a pretty blunt instrument, and he'd be crazy to use it too often.  Could he have found other weapons?   It sure seems unlikely to me.  More to the point, Obama, like all presidents, had to establish priorities, assess where the votes were, and decide how to use the resources of the presidency.  He had, of course, a long agenda, with various constituencies pushing to have their pet issue and the sub-issues contained within each of those issues placed at the top.  And while he had a lot of assets, including a large majority in the House and (for a very brief period) 60 Democratic Senators, he had a lot of constraints, including all the problems he inherited that had little to do with the long-term Democratic agenda and a fully rejectionist Republican party.  The latter -- and really, it takes a complete misunderstanding of how the American political system works not to see this -- means that individual Democratic Senators hold a great deal of bargaining power over the president.  Not, alas for Obama and for the liberal agenda, the other way around.

The most amusing thing about those on the left and the right who think their party leaders are sell-outs is how unaware they are of their resemblance to each other. The conservative movement is filled with people who think George W. Bush failed to cut spending because he lacked sufficient willpower to demand it. Very few of them understand, say, that Bush had to support some kind of prescription drug bill to win in 2000 and had to follow through on his promise to win in 2004. They believe the problem was that Bush was insufficiently committed to their ideological goals. Time to replace him with a true believer!