Because it is finally in Congress' interest to make it happen:
This election was about Iraq. Period. The exit polls may have listed corruption pretty high. Mike Pence may think that Republicans lost because they didn’t cut Medicaid enough. But they lost because of Iraq. And it was a stunning, two-by-four-to-the-face rebuke to what is generously known as Bush’s Iraq policy. Yes, it could have been worse for the GOP. But the mere fact that so many of these “safe” districts were close was itself a rebuke of the current Iraq policy.
... But the election will affect things for the better and for a very specific reason – the election has finally aligned politics and policy. In other words, the election has created political incentives for legislators to demand and implement change. Better policy is now politically rational, and sticking to bad policy is politically irrational.
To take a step back, I’ve developed a very cynical view of the motivations of our elected officials. I see them as purely rational actors. Everything that they do (as opposed to what they say) is motivated solely by the hopes of political benefit or the fear of political harm. Morals, patriotism, and other abstract concepts have no explanatory power in my world. If you want politicians to fix something, then you make them fear not fixing it. If you want to them to stop doing something, you make them fear not stopping it.
... Early in the summer of 2006, the magnitude of the failures in Iraq was even clearer than in 2004. ... But rather than do anything to try to force the administration to change, they all adopted the Super Genius’s strategy to run on “stay the course” in Iraq. That is, until the Democrats – in the move that won them the election – flipped it back on them. The cynicism of this initial strategy was breathtaking, and borders on black comedy. But it wasn’t irrational. At that moment, their inaction had only been rewarded. It had never been punished.
That’s why it’s a bit rich to hear poor Susan Collins moaning that the mean ol’ Democrats attacked “Linc” too hard. Susan Collins – sitting atop an important oversight committee – hasn’t lifted a finger in four years to demand accountability. Susan Collins has done precisely nothing to stop a policy that she surely knows is an absolute and complete failure. And neither have the rest of them. But again, you can’t really put all the blame on them. The voters didn’t make this sort of outrageousness a political liability.
And that’s what so great about it. In the grand scheme of things, what’s really important is not so much that the Democrats won, but how they won. By frontally attacking the GOP on “stay the course,” they made staying the course a political liability....
The bottom line is that, because of yesterday’s elections, legislators now have political incentives to change the course. It is rational for them to demand change. We no longer have to rely on their morals, or their reason, or their regard for the troops. We can rely on their desire to save their own ass, which is the best guarantee we can possibly have.
And you’re going to see this dynamic in the Senate too. Don’t think that this bloc of Southern Senators facing re-election in 2008 didn’t get a chill up their spine when the press declared Webb the winner. If a political nobody can beat a popular former governor and presidential candidate over Iraq in a Southern state, then they can get beat too. And they know it – and so they too will demand change.