Why do Senate Democrats let themselves get punked?

Greenwald, who is almost always worth reading:

But it isn't true that there is a "60-vote requirement," [to get anything done in the Senate] because only Republicans are willing to impose it. Democrats won't, even on what they claim are the gravest of matters, such as confirming someone as Attorney General who is "dead wrong on torture" and who won't even "tell the president that he cannot ignore the laws passed by Congress."

The so-called "60-vote requirement" applies only when it is time to do something to limit the Bush administration. It is merely the excuse Senate Democrats use to explain away their chronic failure/unwillingness to limit the President, and it is what the media uses to depict the GOP filibuster as something normal and benign. There obviously is no "60-vote requirement" when it comes to having the Senate comply with the President's demands, as the 53-vote confirmation of Michael Mukasey amply demonstrates. But as Mukasey is sworn in as the highest law enforcement officer in America, the Democrats want you to know that they most certainly did stand firm and "registered their displeasure."

Well, allow me to "register my displeasure" with the Democrats of the Senate (especially Schumer and Feinstein), since unlike them, I can't filibuster nominees for Attorney General who hem and haw on whether waterboarding is torture or not.